title: "Ice hockey" content: student at King's College School in that town in 1810 and earlier. Based on Haliburton's quote, claims were made that modern hockey was invented in Windsor, Nova Scotia, by King's College students and perhaps named after an individual ("Colonel Hockey's game"). Others claim that the origins of hockey come from games played in the area of Dartmouth and Halifax in Nova Scotia. However, several references have been found to hurling and shinty being played on the ice long before the earliest references from both Windsor and Dartmouth/Halifax, and the word "hockey" was used to designate a stick-and-ball game at least


title: "Ice hockey" content: as far back as 1773, as it was mentioned in the book "Juvenile Sports and Pastimes, to Which Are Prefixed, Memoirs of the Author: Including a New Mode of Infant Education" by Richard Johnson (Pseud. Master Michel Angelo), whose chapter XI was titled "New Improvements on the Game of Hockey". While the game's origins lie elsewhere, Montreal is at the centre of the development of the sport of contemporary ice hockey, and is recognized as the birthplace of organized ice hockey. On March 3, 1875, the first organized indoor game was played at Montreal's Victoria Skating Rink between two nine-player


title: "Ice hockey" content: teams, including James Creighton and several McGill University students. Instead of a ball or bung, the game featured a "flat circular piece of wood" (to keep it in the rink and to protect spectators). The goal posts were apart (today's goals are six feet wide). In 1876, games played in Montreal were "conducted under the 'Hockey Association' rules"; the Hockey Association was England's field hockey organization. In 1877, "The Gazette" (Montreal) published a list of seven rules, six of which were largely based on six of the Hockey Association's twelve rules, with only minor differences (even the word "ball" was


title: "Ice hockey" content: kept); the one added rule explained how disputes should be settled. The McGill University Hockey Club, the first ice hockey club, was founded in 1877 (followed by the Quebec Hockey Club in 1878 and the Montreal Victorias in 1881). In 1880, the number of players per side was reduced from nine to seven. The number of teams grew, enough to hold the first "world championship" of ice hockey at Montreal's annual Winter Carnival in 1883. The McGill team won the tournament and was awarded the "Carnival Cup". The game was divided into thirty-minute halves. The positions were now named: left


title: "Ice hockey" content: and right wing, centre, rover, point and cover-point, and goaltender. In 1886, the teams competing at the Winter Carnival organized the Amateur Hockey Association of Canada (AHAC), and played a season comprising "challenges" to the existing champion. In Europe, it is believed that in 1885 the Oxford University Ice Hockey Club was formed to play the first Ice Hockey Varsity Match against traditional rival Cambridge in St. Moritz, Switzerland; however, this is undocumented. The match was won by the Oxford Dark Blues, 6–0; the first photographs and team lists date from 1895. This rivalry continues, claiming to be the oldest


title: "Ice hockey" content: hockey rivalry in history; a similar claim is made about the rivalry between Queen's University and Royal Military College of Kingston, Ontario. Since 1986, considered the 100th anniversary of the rivalry, teams of the two colleges play for the Carr-Harris Cup. In 1888, the Governor General of Canada, Lord Stanley of Preston (whose sons and daughter were hockey enthusiasts), first attended the Montreal Winter Carnival tournament and was impressed with the game. In 1892, realizing that there was no recognition for the best team in Canada (although a number of leagues had championship trophies), he purchased a silver bowl for


title: "Ice hockey" content: use as a trophy. The Dominion Hockey Challenge Cup (which later became known as the Stanley Cup) was first awarded in 1893 to the Montreal Hockey Club, champions of the AHAC; it continues to be awarded annually to the National Hockey League's championship team. Stanley's son Arthur helped organize the Ontario Hockey Association, and Stanley's daughter Isobel was one of the first women to play ice hockey. By 1893, there were almost a hundred teams in Montreal alone; in addition, there were leagues throughout Canada. Winnipeg hockey players used cricket pads to better protect the goaltender's legs; they also introduced


title: "Ice hockey" content: the "scoop" shot, or what is now known as the wrist shot. William Fairbrother, from Ontario, Canada is credited with inventing the ice hockey net in the 1890s. Goal nets became a standard feature of the Canadian Amateur Hockey League (CAHL) in 1900. Left and right defence began to replace the point and cover-point positions in the OHA in 1906. In the United States, "ice polo", played with a ball rather than a puck, was popular during this period; however, by 1893 Yale University and Johns Hopkins University held their first ice hockey matches. American financier Malcolm Greene Chace is


title: "Ice hockey" content: credited with being the father of hockey in the United States. In 1892, as an amateur tennis player, Chace visited Niagara Falls, New York for a tennis match, where he met some Canadian hockey players. Soon afterwards, Chace put together a team of men from Yale, Brown, and Harvard, and toured across Canada as captain of this team. The first collegiate hockey match in the United States was played between Yale University and Johns Hopkins in Baltimore. Yale, led by captain Chace, beat Hopkins, 2–1. In 1896, the first ice hockey league in the US was formed. The US Amateur


title: "Ice hockey" content: Hockey League was founded in New York City, shortly after the opening of the artificial-ice St. Nicholas Rink. Lord Stanley's five sons were instrumental in bringing ice hockey to Europe, defeating a court team (which included the future Edward VII and George V) at Buckingham Palace in 1895. By 1903, a five-team league had been founded. The "Ligue Internationale de Hockey sur Glace" was founded in 1908 to govern international competition, and the first European championship was won by Great Britain in 1910. The sport grew further in Europe in the 1920s, after ice hockey became an Olympic sport. Many


title: "Ice hockey" content: bandy players switched to hockey so as to be able to compete in the Olympics. Bandy remained popular in the Soviet Union, which only started its ice hockey program in the 1950s. In the mid-20th century, the "Ligue" became the International Ice Hockey Federation. As the popularity of ice hockey as a spectator sport grew, earlier rinks were replaced by larger rinks. Most of the early indoor ice rinks have been demolished; Montreal's Victoria Rink, built in 1862, was demolished in 1925. Many older rinks succumbed to fire, such as Denman Arena, Dey's Arena, Quebec Skating Rink and Montreal Arena,


title: "Ice hockey" content: a hazard of the buildings' wood construction. The Stannus Street Rink in Windsor, Nova Scotia (built in 1897) may be the oldest still in existence; however, it is no longer used for hockey. The Aberdeen Pavilion (built in 1898) in Ottawa was used for hockey in 1904 and is the oldest existing facility that has hosted Stanley Cup games. The oldest indoor ice hockey arena still in use today for hockey is Boston's Matthews Arena, which was built in 1910. It has been modified extensively several times in its history and is used today by Northeastern University for hockey and


title: "Ice hockey" content: other sports. It was the original home rink of the Boston Bruins professional team, itself the oldest United States-based team in the NHL, starting play in the league in today's Matthews Arena on December 1, 1924. Madison Square Garden in New York City, built in 1968, is the oldest continuously-operating arena in the NHL. Professional hockey has existed since the early 20th century. By 1902, the Western Pennsylvania Hockey League was the first to employ professionals. The league joined with teams in Michigan and Ontario to form the first fully professional league—the International Professional Hockey League (IPHL)—in 1904. The WPHL


title: "Ice hockey" content: and IPHL hired players from Canada; in response, Canadian leagues began to pay players (who played with amateurs). The IPHL, cut off from its largest source of players, disbanded in 1907. By then, several professional hockey leagues were operating in Canada (with leagues in Manitoba, Ontario and Quebec). In 1910, the National Hockey Association (NHA) was formed in Montreal. The NHA would further refine the rules: dropping the rover position, dividing the game into three 20-minute periods and introducing minor and major penalties. After re-organizing as the National Hockey League in 1917, the league expanded into the United States, starting


title: "Ice hockey" content: with the Boston Bruins in 1924. Professional hockey leagues developed later in Europe, but amateur leagues leading to national championships were in place. One of the first was the Swiss National League A, founded in 1916. Today, professional leagues have been introduced in most countries of Europe. Top European leagues include the Kontinental Hockey League, the Czech Extraliga, the Finnish Liiga and the Swedish Hockey League. While the general characteristics of the game stay the same wherever it is played, the exact rules depend on the particular code of play being used. The two most important codes are those of


title: "Ice hockey" content: the IIHF and the NHL. Both of the codes, and others, originated from Canadian rules of ice hockey of the early 20th Century. Ice hockey is played on a "hockey rink". During normal play, there are six players per side on the ice at any time, one of them being the goaltender, each of whom is on ice skates. The objective of the game is to score "goals" by shooting a hard vulcanized rubber disc, the "puck", into the opponent's goal net, which is placed at the opposite end of the rink. The players use their sticks to pass or


title: "Ice hockey" content: shoot the puck. Within certain restrictions, players may redirect the puck with any part of their body. Players may not hold the puck in their hand and are prohibited from using their hands to pass the puck to their teammates, unless they are in the defensive zone. Players are also prohibited from kicking the puck into the opponent's goal, though unintentional redirections off the skate are permitted. Players may not intentionally bat the puck into the net with their hands. Hockey is an "off-side" game, meaning that forward passes are allowed, unlike in rugby. Before the 1930s hockey was an


title: "Ice hockey" content: on-side game, meaning that only backward passes were allowed. Those rules favoured individual stick-handling as a key means of driving the puck forward. With the arrival of offside rules, the forward pass transformed hockey into a truly team sport, where individual performance diminished in importance relative to team play, which could now be coordinated over the entire surface of the ice as opposed to merely rearward players. The six players on each team are typically divided into three forwards, two defencemen, and a goaltender. The term "skaters" is typically used to describe all players who are not goaltenders. The "forward"


title: "Ice hockey" content: positions consist of a "centre" and two "wingers": a "left wing" and a "right wing". Forwards often play together as units or "lines", with the same three forwards always playing together. The "defencemen" usually stay together as a pair generally divided between left and right. Left and right side wingers or defencemen are generally positioned as such, based on the side on which they carry their stick. A substitution of an entire unit at once is called a "line change". Teams typically employ alternate sets of forward lines and defensive pairings when "shorthanded" or on a "power play". The goaltender


title: "Ice hockey" content: stands in a, usually blue, semi-circle called the "crease" in the defensive zone keeping pucks from going in. Substitutions are permitted at any time during the game, although during a stoppage of play the home team is permitted the final change. When players are substituted during play, it is called changing "on the fly". A new NHL rule added in the 2005–06 season prevents a team from changing their line after they "ice" the puck. The boards surrounding the ice help keep the puck in play and they can also be used as tools to play the puck. Players are


title: "Ice hockey" content: permitted to "bodycheck" opponents into the boards as a means of stopping progress. The referees, linesmen and the outsides of the goal are "in play" and do not cause a stoppage of the game when the puck or players are influenced (by either bouncing or colliding) into them. Play can be stopped if the goal is knocked out of position. Play often proceeds for minutes without interruption. When play is stopped, it is restarted with a "faceoff". Two players "face" each other and an official drops the puck to the ice, where the two players attempt to gain control of


title: "Ice hockey" content: the puck. Markings (circles) on the ice indicate the locations for the faceoff and guide the positioning of players. The three major rules of play in ice hockey that limit the movement of the puck: "offside", "icing", and the puck going out of play. A player is "offside" if he enters his opponent's zone before the puck itself. Under many situations, a player may not "ice the puck", shoot the puck all the way across both the centre line and the opponent's goal line. The puck goes "out of play" whenever it goes past the perimeter of the ice rink


title: "Ice hockey" content: (onto the player benches, over the "glass," or onto the protective netting above the glass) and a stoppage of play is called by the officials using whistles. It also does not matter if the puck comes back onto the ice surface from those areas as the puck is considered dead once it leaves the perimeter of the rink. Under IIHF rules, each team may carry a maximum of 20 players and two goaltenders on their roster. NHL rules restrict the total number of players per game to 18, plus two goaltenders. In the NHL, the players are usually divided into


title: "Ice hockey" content: four lines of three forwards, and into three pairs of defencemen. On occasion, teams may elect to substitute an extra defenceman for a forward. The seventh defenceman may play as a substitute defenceman, spend the game on the bench, or if a team chooses to play four lines then this seventh defenceman may see ice-time on the fourth line as a forward. A professional game consists of three "periods" of twenty minutes, the clock running only when the puck is in play. The teams change ends after each period of play, including overtime. Recreational leagues and children's leagues often play


title: "Ice hockey" content: shorter games, generally with three shorter periods of play. Various procedures are used if a tie occurs. In tournament play, as well as in the NHL playoffs, North Americans favour "sudden death overtime", in which the teams continue to play twenty-minute periods until a goal is scored. Up until the 1999–2000 season regular season NHL games were settled with a single five-minute sudden death period with five players (plus a goalie) per side, with both teams awarded one point in the standings in the event of a tie. With a goal, the winning team would be awarded two points and


title: "Ice hockey" content: the losing team none (just as if they had lost in regulation). From 1999–2000 until 2003–04, the National Hockey League decided ties by playing a single five-minute sudden death overtime period with each team having four skaters per side (plus the goalie) to "open up" the game. In the event of a tie, each team would still receive one point in the standings but in the event of a victory the winning team would be awarded two points in the standings and the losing team one point. The idea was to discourage teams from playing for a tie, since previously


title: "Ice hockey" content: some teams might have preferred a tie and 1 point to risking a loss and zero points. The only exception to this rule is if a team opts to pull their goalie in exchange for an extra skater during overtime and is subsequently scored upon (an "empty net" goal), in which case the losing team receives no points for the overtime loss. Since the 2015–16 season, the single five-minute sudden death overtime session involves three skaters on each side. Since three skaters must always be on the ice in an NHL game, the consequences of penalties are slightly different from


title: "Ice hockey" content: those during regulation play. If a team is on a powerplay when overtime begins, that team will play with more than three skaters (usually four, very rarely five) until the expiration of the penalty. Any penalty during overtime that would result in a team losing a skater during regulation instead causes the non-penalized team to add a skater. Once the penalized team's penalty ends, the number of skaters on each side is adjusted accordingly, with the penalized team adding a skater in regulation and the non-penalized team subtracting a skater in overtime. This goes until the next stoppage of play.


title: "Ice hockey" content: International play and several North American professional leagues, including the NHL (in the regular season), now use an overtime period identical to that from 99–00 – 03–04 followed by a penalty shootout. If the score remains tied after an extra overtime period, the subsequent shootout consists of three players from each team taking penalty shots. After these six total shots, the team with the most goals is awarded the victory. If the score is still tied, the shootout then proceeds to a "sudden death" format. Regardless of the number of goals scored during the shootout by either team, the final


title: "Ice hockey" content: score recorded will award the winning team one more goal than the score at the end of regulation time. In the NHL if a game is decided in overtime or by a shootout the winning team is awarded two points in the standings and the losing team is awarded one point. Ties no longer occur in the NHL. The overtime mode for the NHL playoffs differ from the regular season. In the playoffs there are no shootouts nor ties. If a game is tied after regulation an additional 20 minutes of 5 on 5 sudden death overtime will be added.


title: "Ice hockey" content: In case of a tied game after the overtime, multiple 20-minute overtimes will be played until a team scores, which wins the match. In ice hockey, infractions of the rules lead to play stoppages whereby the play is restarted at a face off. Some infractions result in the imposition of a "penalty" to a player or team. In the simplest case, the offending player is sent to the "penalty box" and their team has to play with one less player on the ice for a designated amount of time. "Minor" penalties last for two minutes, "major" penalties last for five


title: "Ice hockey" content: minutes, and a "double minor" penalty is two "consecutive" penalties of two minutes duration. A single minor penalty may be extended by a further two minutes for causing visible injury to the victimized player. This is usually when blood is drawn during high sticking. Players may be also assessed personal extended penalties or game expulsions for misconduct in addition to the penalty or penalties their team must serve. The team that has been given a penalty is said to be playing "short-handed" while the opposing team is on a "power play". A two-minute minor penalty is often charged for lesser


title: "Ice hockey" content: infractions such as "tripping", "elbowing", "roughing", "high-sticking", "delay of the game", "too many players on the ice", "boarding", illegal equipment, "charging" (leaping into an opponent or body-checking him after taking more than two strides), "holding", holding the stick (grabbing an opponent's stick), "interference", "hooking", "slashing", "kneeing", "unsportsmanlike conduct" (arguing a penalty call with referee, extremely vulgar or inappropriate verbal comments), "butt-ending" (striking an opponent with the knob of the stick—a very rare penalty), "spearing", or "cross-checking". As of the 2005–2006 season, a minor penalty is also assessed for "diving", where a player embellishes or simulates an offence. More egregious fouls


title: "Ice hockey" content: may be penalized by a four-minute double-minor penalty, particularly those that injure the victimized player. These penalties end either when the time runs out or when the other team scores during the power play. In the case of a goal scored during the first two minutes of a double-minor, the penalty clock is set down to two minutes upon a score, effectively expiring the first minor penalty. Five-minute major penalties are called for especially violent instances of most minor infractions that result in intentional injury to an opponent, or when a "minor" penalty results in visible injury (such as bleeding),


title: "Ice hockey" content: as well as for fighting. Major penalties are always served in full; they do not terminate on a goal scored by the other team. Major penalties assessed for fighting are typically offsetting, meaning neither team is short-handed and the players exit the penalty box upon a stoppage of play following the expiration of their respective penalties. The foul of "boarding" (defined as "check[ing] an opponent in such a manner that causes the opponent to be thrown violently in the boards") is penalized either by a minor or major penalty at the discretion of the referee, based on the violent state


title: "Ice hockey" content: of the hit. A minor or major penalty for boarding is often assessed when a player checks an opponent from behind and into the boards. Some varieties of penalties do not always require the offending team to play a man short. Concurrent five-minute major penalties in the NHL usually result from fighting. In the case of two players being assessed five-minute fighting majors, both the players serve five minutes without their team incurring a loss of player (both teams still have a full complement of players on the ice). This differs with two players from opposing sides getting minor penalties,


title: "Ice hockey" content: at the same time or at any intersecting moment, resulting from more common infractions. In this case, both teams will have only four skating players (not counting the goaltender) until one or both penalties expire (if one penalty expires before the other, the opposing team gets a power play for the remainder of the time); this applies regardless of current pending penalties. However, in the NHL, a team always has at least three skaters on the ice. Thus, ten-minute "misconduct" penalties are served in full by the penalized player, but his team may immediately substitute another player on the ice


title: "Ice hockey" content: "unless" a minor or major penalty is assessed in conjunction with the misconduct (a "two-and-ten" or "five-and-ten"). In this case, the team designates another player to serve the minor or major; both players go to the penalty box, but only the designee may not be replaced, and he is released upon the expiration of the two or five minutes, at which point the ten-minute misconduct begins. In addition, "game misconducts" are assessed for deliberate intent to inflict severe injury on an opponent (at the officials' discretion), or for a major penalty for a stick infraction or repeated major penalties. The


title: "Ice hockey" content: offending player is ejected from the game and must immediately leave the playing surface (he does not sit in the penalty box); meanwhile, if an additional minor or major penalty is assessed, a designated player must serve out of that segment of the penalty in the box (similar to the above-mentioned "two-and-ten"). In some rare cases, a player may receive up to nineteen minutes in penalties for one string of plays. This could involve receiving a four-minute double minor penalty, getting in a fight with an opposing player who retaliates, and then receiving a game misconduct after the fight. In


title: "Ice hockey" content: this case, the player is ejected and two teammates must serve the double-minor and major penalties. A "penalty shot" is awarded to a player when the illegal actions of another player stop a clear scoring opportunity, most commonly when the player is on a "breakaway". A penalty shot allows the obstructed player to pick up the puck on the centre red-line and attempt to score on the goalie with no other players on the ice, to compensate for the earlier missed scoring opportunity. A penalty shot is also awarded for a defender other than the goaltender covering the puck in


title: "Ice hockey" content: the goal crease, a goaltender intentionally displacing his own goal posts during a breakaway to avoid a goal, a defender intentionally displacing his own goal posts when there is less than two minutes to play in regulation time or at any point during overtime, or a player or coach intentionally throwing a stick or other object at the puck or the puck carrier and the throwing action disrupts a shot or pass play. Officials also stop play for puck movement violations, such as using one's hands to pass the puck in the offensive end, but no players are penalized for


title: "Ice hockey" content: these offences. The sole exceptions are deliberately falling on or gathering the puck to the body, carrying the puck in the hand, and shooting the puck out of play in one's defensive zone (all penalized two minutes for delay of game). In the NHL, a unique penalty applies to the goalies. The goalies now are forbidden to play the puck in the "corners" of the rink near their own net. This will result in a two-minute penalty against the goalie's team. Only in the area in-front of the goal line and immediately behind the net (marked by two red lines


title: "Ice hockey" content: on either side of the net) the goalie can play the puck. An additional rule that has never been a penalty, but was an infraction in the NHL before recent rules changes, is the "two-line offside pass". Prior to the 2005–06 NHL season, play was stopped when a pass from inside a team's defending zone crossed the centre line, with a face-off held in the defending zone of the offending team. Now, the centre line is no longer used in the NHL to determine a two-line pass infraction, a change that the IIHF had adopted in 1998. Players are now


title: "Ice hockey" content: able to pass to teammates who are more than the blue and centre ice red line away. The NHL has taken steps to speed up the game of hockey and create a game of finesse, by retreating from the past when illegal hits, fights, and "clutching and grabbing" among players were commonplace. Rules are now more strictly enforced, resulting in more penalties, which in turn provides more protection to the players and facilitates more goals being scored. The governing body for United States' amateur hockey has implemented many new rules to reduce the number of stick-on-body occurrences, as well as


title: "Ice hockey" content: other detrimental and illegal facets of the game ("zero tolerance"). In men's hockey, but not in women's, a player may use his hip or shoulder to hit another player if the player has the puck or is the last to have touched it. This use of the hip and shoulder is called "body checking". Not all physical contact is legal—in particular, hits from behind, hits to the head and most types of forceful stick-on-body contact are illegal. A "delayed penalty call" occurs when a penalty offence is committed by the team that does not have possession of the puck. In


title: "Ice hockey" content: this circumstance the team with possession of the puck is allowed to complete the play; that is, play continues until a goal is scored, a player on the opposing team gains control of the puck, or the team in possession commits an infraction or penalty of their own. Because the team on which the penalty was called cannot control the puck without stopping play, it is impossible for them to score a goal. In these cases, the team in possession of the puck can pull the goalie for an extra attacker without fear of being scored on. However, it is


title: "Ice hockey" content: possible for the controlling team to mishandle the puck into their own net. If a delayed penalty is signalled and the team in possession scores, the penalty is still assessed to the offending player, but not served. In 2012, this rule was changed by the United States' National Collegiate Athletic Association (NCAA) for college level hockey. In college games, the penalty is still enforced even if the team in possession scores. A typical game of hockey is governed by two to four "officials" on the ice, charged with enforcing the rules of the game. There are typically two "linesmen" who


title: "Ice hockey" content: are mainly responsible for calling "offside" and "icing" violations, breaking up fights, and conducting faceoffs, and one or two "referees", who call goals and all other penalties. Linesmen can, however, report to the referee(s) that a penalty should be assessed against an offending player in some situations. The restrictions on this practice vary depending on the governing rules. On-ice officials are assisted by off-ice officials who act as goal judges, time keepers, and official scorers. The most widespread system in use today is the "three-man system," that uses one referee and two linesmen. Another less commonly used system is the


title: "Ice hockey" content: two referee and one linesman system. This system is very close to the regular three-man system except for a few procedure changes. With the first being the National Hockey League, a number of leagues have started to implement the "four-official system," where an additional referee is added to aid in the calling of penalties normally difficult to assess by one single referee. The system is now used in every NHL game, at IIHF World Championships, the Olympics and in many professional and high-level amateur leagues in North America and Europe. Officials are selected by the league they work for. Amateur


title: "Ice hockey" content: hockey leagues use guidelines established by national organizing bodies as a basis for choosing their officiating staffs. In North America, the national organizing bodies Hockey Canada and USA Hockey approve officials according to their experience level as well as their ability to pass rules knowledge and skating ability tests. Hockey Canada has officiating levels I through VI. USA Hockey has officiating levels 1 through 4. Since men's ice hockey is a full contact sport, body checks are allowed so injuries are a common occurrence. Protective equipment is mandatory and is enforced in all competitive situations. This includes a helmet (cage


title: "Ice hockey" content: worn if certain age or clear plastic visor can be worn), shoulder pads, elbow pads, mouth guard, protective gloves, heavily padded shorts (also known as hockey pants) or a girdle, athletic cup (also known as a jock, for males; and jill, for females), shin pads, skates, and (optionally) a neck protector. Goaltenders use different equipment. With hockey pucks approaching them at speeds of up to 100 mph (160 km/h) they must wear equipment with more protection. Goaltenders wear specialized goalie skates (these skates are built more for movement side to side rather than forwards and backwards), a jock or jill,


title: "Ice hockey" content: large leg pads (there are size restrictions in certain leagues), blocking glove, catching glove, a chest protector, a goalie mask, and a large jersey. Goaltenders' equipment has continually become larger and larger, leading to fewer goals in each game and many official rule changes. Hockey skates are optimized for physical acceleration, speed and manoeuvrability. This includes rapid starts, stops, turns, and changes in skating direction. In addition, they must be rigid and tough to protect the skater's feet from contact with other skaters, sticks, pucks, the boards, and the ice itself. Rigidity also improves the overall manoeuvrability of the skate.


title: "Ice hockey" content: Blade length, thickness (width), and curvature (rocker/radius (front to back) and radius of hollow (across the blade width) are quite different from speed or figure skates. Hockey players usually adjust these parameters based on their skill level, position, and body type. The blade width of most skates are about thick. The hockey stick consists of a long, relatively wide, and slightly curved flat blade, attached to a shaft. The curve itself has a big impact on its performance. A deep curve allows for lifting the puck easier while a shallow curve allows for easier backhand shots. The flex of the


title: "Ice hockey" content: stick also impacts the performance. Typically, a less flexible stick is meant for a stronger player since the player is looking for the right balanced flex that allows the stick to flex easily while still having a strong "whip-back" which sends the puck flying at high speeds. It is quite distinct from sticks in other sports games and most suited to hitting and controlling the flat puck. Its unique shape contributed to the early development of the game. Ice hockey is a full contact sport and carries a high risk of injury. Players are moving at speeds around approximately and


title: "Ice hockey" content: quite a bit of the game revolves around the physical contact between the players. Skate blades, hockey sticks, shoulders, hips, and hockey pucks all contribute. The types of injuries associated with hockey include: lacerations, concussions, contusions, ligament tears, broken bones, hyperextensions, and muscle strains. Women's ice hockey players can have contact but are not allowed to body check. Compared to athletes who play other sports, ice hockey players are at higher risk of overuse injuries and injuries caused by early sports specialization by teenagers. According to the Hughston Health Alert, "Lacerations to the head, scalp, and face are the most


title: "Ice hockey" content: frequent types of injury [in hockey]." Even a shallow cut to the head results in a loss of a large amount of blood. Not only are lacerations common, "it is estimated that direct trauma accounts for 80% of all [hockey] injuries. Most of these injuries are caused by player contact, falls and contact with a puck, high stick and occasionally, a skate blade." One of the causes of head injury is checking from behind. Due to the danger of delivering a check from behind, many leagues, including the NHL have made this a major and game misconduct penalty (called "boarding").


title: "Ice hockey" content: Another type of check that accounts for many of the player-to-player contact concussions is a check to the head resulting in a misconduct penalty (called "head contact"). A check to the head can be defined as delivering a hit while the receiving player's head is down and their waist is bent and the aggressor is targeting the opponent player's head. The most dangerous result of a head injury in hockey can be classified as a concussion. Most concussions occur during player-to-player contact rather than when a player is checked into the boards. Checks to the head have accounted for nearly


title: "Ice hockey" content: 50% of concussions that players in the National Hockey League have suffered. Concussions that players suffer may go unreported because there is no obvious physical signs if a player is not knocked unconscious. This can prove to be dangerous if a player decides to return to play without receiving proper medical attention. Studies show that, ice hockey causes 44.3% of all traumatic brain injuries among Canadian children. In severe cases, the traumatic brain injuries are capable of resulting in death. Occurrences of death from these injuries are rare, but occur all too much in a variety of sports. An important


title: "Ice hockey" content: defensive tactic is checking—attempting to take the puck from an opponent or to remove the opponent from play. "Stick checking", "sweep checking", and "poke checking" are legal uses of the stick to obtain possession of the puck. The "neutral zone trap" is designed to isolate the puck carrier in the neutral zone preventing him from entering the offensive zone. "Body checking" is using one's shoulder or hip to strike an opponent who has the puck or who is the last to have touched it (the last person to have touched the puck is still legally "in possession" of it, although


title: "Ice hockey" content: a penalty is generally called if he is checked more than two seconds after his last touch). Often the term checking is used to refer to body checking, with its true definition generally only propagated among fans of the game. Offensive tactics include improving a team's position on the ice by advancing the puck out of one's zone towards the opponent's zone, progressively by gaining lines, first your own blue line, then the red line and finally the opponent's blue line. NHL rules instated for the 2006 season redefined the offside rule to make the two-line pass legal; a player


title: "Ice hockey" content: may pass the puck from behind his own blue line, past both that blue line and the centre red line, to a player on the near side of the opponents' blue line. Offensive tactics are designed ultimately to score a goal by taking a shot. When a player purposely directs the puck towards the opponent's goal, he or she is said to "shoot" the puck. A "deflection" is a shot that redirects a shot or a pass towards the goal from another player, by allowing the puck to strike the stick and carom towards the goal. A "one-timer" is a


title: "Ice hockey" content: shot struck directly off a pass, without receiving the pass and shooting in two separate actions. "Headmanning the puck", also known as "breaking out", is the tactic of rapidly passing to the player farthest down the ice. "Loafing", also known as "cherry-picking", is when a player, usually a forward, skates behind an attacking team, instead of playing defence, in an attempt to create an easy scoring chance. A team that is losing by one or two goals in the last few minutes of play will often elect to "pull the goalie"; that is, remove the goaltender and replace him or


title: "Ice hockey" content: her with an "extra attacker" on the ice in the hope of gaining enough advantage to score a goal. However, it is an act of desperation, as it sometimes leads to the opposing team extending their lead by scoring a goal in the empty net. One of the most important strategies for a team is their "forecheck". Forechecking is the act of attacking the opposition in their defensive zone. Forechecking is an important part of the "dump and chase" strategy (i.e. shooting the puck into the offensive zone and then chasing after it). Each team will use their own unique


title: "Ice hockey" content: system but the main ones are: 2–1–2, 1–2–2, and 1–4. The 2–1–2 is the most basic forecheck system where two forwards will go in deep and pressure the opposition's defencemen, the third forward stays high and the two defencemen stay at the blueline. The 1–2–2 is a bit more conservative system where one forward pressures the puck carrier and the other two forwards cover the oppositions' wingers, with the two defencemen staying at the blueline. The 1–4 is the most defensive forecheck system, referred to as the neutral zone trap, where one forward will apply pressure to the puck carrier


title: "Ice hockey" content: around the oppositions' blueline and the other 4 players stand basically in a line by their blueline in hopes the opposition will skate into one of them. Another strategy is the left wing lock, which has two forwards pressure the puck and the left wing and the two defencemen stay at the blueline. There are many other little tactics used in the game of hockey. "Cycling" moves the puck along the boards in the offensive zone to create a scoring chance by making defenders tired or moving them out of position. "Pinching" is when a defenceman pressures the opposition's winger


title: "Ice hockey" content: in the offensive zone when they are breaking out, attempting to stop their attack and keep the puck in the offensive zone. A "saucer pass" is a pass used when an opposition's stick or body is in the passing lane. It is the act of raising the puck over the obstruction and having it land on a teammate's stick. A deke, short for "decoy," is a feint with the body or stick to fool a defender or the goalie. Many modern players, such as Pavel Datsyuk, Sidney Crosby and Patrick Kane, have picked up the skill of "dangling," which is


title: "Ice hockey" content: fancier deking and requires more stick handling skills. Although fighting is officially prohibited in the rules, it is not an uncommon occurrence at the professional level, and its prevalence has been both a target of criticism and a considerable draw for the sport. At the professional level in North America fights are unofficially condoned. Enforcers and other players fight to demoralize the opposing players while exciting their own, as well as settling personal scores. A fight will also break out if one of the team's skilled players gets hit hard or someone gets hit by what the team perceives as


title: "Ice hockey" content: a dirty hit. The amateur game penalizes fisticuffs more harshly, as a player who receives a fighting major is also assessed at least a 10-minute misconduct penalty (NCAA and some Junior leagues) or a game misconduct penalty and suspension (high school and younger, as well as some casual adult leagues). Crowds seem to like fighting in ice hockey and cheer when fighting erupts. Ice hockey is one of the fastest growing women's sports in the world, with the number of participants increasing by 400 percent from 1995 to 2005. In 2011, Canada had 85,827 women players, United States had 65,609,


title: "Ice hockey" content: Finland 4,760, Sweden 3,075 and Switzerland 1,172. While there are not as many organized leagues for women as there are for men, there exist leagues of all levels, including the Canadian Women's Hockey League (CWHL), Western Women's Hockey League, National Women's Hockey League (NWHL), Mid-Atlantic Women's Hockey League, and various European leagues; as well as university teams, national and Olympic teams, and recreational teams. The IIHF holds IIHF World Women's Championships tournaments in several divisions; championships are held annually, except that the top flight does not play in Olympic years. The chief difference between women's and men's ice hockey is


title: "Ice hockey" content: that body checking is prohibited in women's hockey. After the 1990 Women's World Championship, body checking was eliminated in women's hockey. In current IIHF women's competition, body checking is either a minor or major penalty, decided at the referee's discretion. In addition, players in women's competition are required to wear protective full-face masks. In Canada, to some extent ringette has served as the female counterpart to ice hockey, in the sense that traditionally, boys have played hockey while girls have played ringette. Women are known to have played the game in the 19th century. Several games were recorded in the


title: "Ice hockey" content: 1890s in Ottawa, Ontario, Canada. The women of Lord Stanley's family were known to participate in the game of ice hockey on the outdoor ice rink at Rideau Hall, the residence of Canada's Governor-General. The game developed at first without an organizing body. A tournament in 1902 between Montreal and Trois-Rivieres was billed as the first championship tournament. Several tournaments, such as at the Banff Winter Carnival, were held in the early 20th century and numerous women's teams such as the Seattle Vamps and Vancouver Amazons existed. Organizations started to develop in the 1920s, such as the Ladies Ontario Hockey


title: "Ice hockey" content: Association, and later, the Dominion Women's Amateur Hockey Association. Starting in the 1960s, the game spread to universities. Today, the sport is played from youth through adult leagues, and in the universities of North America and internationally. There are two major women's hockey leagues, the National Women's Hockey League with teams in the Northeastern United States which is a professional league and the Canadian Women's Hockey League with teams in Canada and the United States, which is semi-professional and is developing toward becoming a fully professional league. The first women's world championship tournament, albeit unofficial, was held in 1987 in


title: "Ice hockey" content: Toronto, Ontario, Canada. This was followed by the first IIHF World Championship in 1990 in Ottawa. Women's ice hockey was added as a medal sport at the 1998 Winter Olympics in Nagano, Japan. The United States won the gold, Canada won the silver and Finland won the bronze medal. The United States won the gold medal again in 2018 at the 2018 Winter Olympics in Pyeongchang, South Korea. The United States Hockey League (USHL) welcomed the first female professional ice hockey player in 1969–70, when the Marquette Iron Rangers signed Karen Koch. One woman, Manon Rhéaume, has played in an


title: "Ice hockey" content: NHL pre-season game as a goaltender for the Tampa Bay Lightning against the St. Louis Blues. In 2003, Hayley Wickenheiser played with the Kirkkonummi Salamat in the Finnish men's Suomi-sarja league. Several women have competed in North American minor leagues, including Rhéaume, goaltenders Kelly Dyer and Erin Whitten and defenceman Angela Ruggiero. With interest in women's ice hockey growing, between 2007 and 2010 the number of registered female players worldwide grew from 153,665 to 170,872. Women's hockey is on the rise in almost every part of the world and there are teams in North America, Europe, Asia, Oceania, Africa and


title: "Ice hockey" content: Latin America. There are currently two North American based professional women's hockey leagues, the Canadian Women's Hockey League (CWHL) and the National Women's Hockey League (NWHL). The CWHL is based in Canada while the NWHL is based in the United States. The CWHL was founded in 2007 and originally consisted of seven teams. As of 2018, there are six teams, although the teams themselves have changed. Currently, the league consists of Worcester Blades, Calgary Inferno, Les Canadiennes de Montreal, Markham Thunder, Shenzhen KRS Vanke Rays, and Toronto Furies. While the CWHL is based in Canada, it does have two teams


title: "Ice hockey" content: that play outside Canada. The Worcester Blades are based in the United States and Shenzhen KRS Vanke Rays are based in China. The NWHL was founded in 2015 and was the first North American women's league to pay its players. The league consists of five teams, though it had four teams for the league's first three seasons. On May 15, 2018, the NWHL announced that the Minnesota Whitecaps would be joining the NWHL starting in the 2018–19 season. The current five teams in the league are the Boston Pride, Buffalo Beauts, Connecticut Whale, Metropolitan Riveters, and Minnesota Whitecaps. The NHL


title: "Ice hockey" content: is by far the best attended and most popular ice hockey league in the world. The league's history began after Canada's National Hockey Association decided to disband in 1917; the result was the creation of the National Hockey League. The league expanded to the United States beginning in 1924. In 1967, the NHL doubled in size to 12 teams, undertaking one of the greatest expansions in professional sports history. A few years later, in 1972, a new 12 team league, the World Hockey Association (WHA) was formed and due to its ensuing rivalry with the NHL, it caused an escalation


title: "Ice hockey" content: in players salaries. As of 1979, the NHL had grown to 17 teams and merged with the WHA. This created a 21 team league. By 2017, the NHL had expanded to 31 teams, and after a realignment in 2013, these teams were divided into two conferences and four divisions. The American Hockey League (AHL), sometimes referred to as "The A," is the primary developmental professional league for players aspiring to enter the NHL. It comprises 30 teams from the United States and Canada, and will expand to 31 teams for the 2018–19 season. It is run as a "farm league"


title: "Ice hockey" content: to the NHL, with the vast majority of AHL players under contract to an NHL team. The ECHL (called the East Coast Hockey League before the 2003–04 season) is a mid-level minor league in the United States with a few players under contract to NHL or AHL teams. The Southern Professional Hockey League (SPHL) is a developmental minor league in the United States with no NHL affiliations. Most undrafted players get their start in the ECHL or SPHL. In the United States especially, college hockey is popular and the best university teams compete in the annual NCAA Men's Ice Hockey


title: "Ice hockey" content: Championship. The American Collegiate Hockey Association is composed of college teams at the club level. In Canada, the Canadian Hockey League is an umbrella organization comprising three major junior leagues: the Ontario Hockey League, the Western Hockey League, and the Quebec Major Junior Hockey League. It attracts players from Canada, the United States and Europe. In the United States, the United States Hockey League (USHL) is the highest junior league. Players in this league are strictly amateur, so that they may play college hockey if they wish. The Kontinental Hockey League (KHL) is the largest and most popular ice hockey


title: "Ice hockey" content: league in Eurasia. The league is the direct successor to the Russian Super League, which in turn was the successor to the Soviet League, the history of which dates back to the Soviet adoption of ice hockey in the 1940s. The KHL was launched in 2008 with clubs predominantly from Russia, but featuring teams from other post-Soviet states. The league expanded beyond the former Soviet countries beginning in the 2011–12 season, with clubs in Croatia and Slovakia. The number of teams has since increased to 28 from eight different countries. The second division of hockey in Eurasia is the Supreme


title: "Ice hockey" content: Hockey League (VHL). This league features 24 teams from Russia and 2 from Kazakhstan. This league is currently being converted to a farm league for the KHL, similarly to the AHL's function in relation to the NHL. The third division is the Russian Hockey League, which features only teams from Russia. The Asia League, an international ice hockey league featuring clubs from China, Japan, South Korea, and the Russian Far East, is the successor to the Japan Ice Hockey League. The highest junior league in Eurasia is the Junior Hockey League (MHL). It features 32 teams from post-Soviet states, predominantly


title: "Ice hockey" content: Russia. The second tier to this league is the Junior Hockey League Championships (MHL-B). Several countries in Europe have their own top professional senior leagues. Many future KHL and NHL players start or end their professional careers in these leagues. The National League A in Switzerland, Swedish Hockey League in Sweden, Liiga in Finland, and Czech Extraliga in the Czech Republic are all very popular in their respective countries. Beginning in the 2014–15 season, the Champions Hockey League was launched, a league consisting of first-tier teams from several European countries, running parallel to the teams' domestic leagues. The competition is


title: "Ice hockey" content: meant to serve as a Europe-wide ice hockey club championship. The competition is a direct successor to the European Trophy and is related to the 2008–09 tournament of the same name. There are also several annual tournaments for clubs, held outside of league play. Pre-season tournaments include the European Trophy, Tampere Cup and the Pajulahti Cup. One of the oldest international ice hockey competition for clubs is the Spengler Cup, held every year in Davos, Switzerland, between Christmas and New Year's Day. It was first awarded in 1923 to the Oxford University Ice Hockey Club. The Memorial Cup, a competition


title: "Ice hockey" content: for junior-level (age 20 and under) clubs is held annually from a pool of junior championship teams in Canada and the United States. International club competitions organized by the IIHF include the Continental Cup, the Victoria Cup and the European Women's Champions Cup. The World Junior Club Cup is an annual tournament of junior ice hockey clubs representing each of the top junior leagues. Ice hockey has been played at the Winter Olympics since 1924 (and was played at the summer games in 1920). Hockey is Canada's national winter sport, and Canadians are extremely passionate about the game. The nation


title: "Ice hockey" content: has traditionally done very well at the Olympic games, winning 6 of the first 7 gold medals. However, by 1956 its amateur club teams and national teams could not compete with the teams of government-supported players from the Soviet Union. The USSR won all but two gold medals from 1956 to 1988. The United States won their first gold medal in 1960. On the way to winning the gold medal at the 1980 Lake Placid Olympics amateur US college players defeated the heavily favoured Soviet squad—an event known as the "Miracle on Ice" in the United States. Restrictions on professional


title: "Ice hockey" content: players were fully dropped at the 1988 games in Calgary. NHL agreed to participate ten years later. 1998 Games saw the full participation of players from the NHL, which suspended operations during the Games and has done so in subsequent Games. The 2010 games in Vancouver were the first played in an NHL city since the inclusion of NHL players. The 2010 games were the first played on NHL-sized ice rinks, which are narrower than the IIHF standard. National teams representing the member federations of the IIHF compete annually in the IIHF Ice Hockey World Championships. Teams are selected from


title: "Ice hockey" content: the available players by the individual federations, without restriction on amateur or professional status. Since it is held in the spring, the tournament coincides with the annual NHL Stanley Cup playoffs and many of the top players are hence not available to participate in the tournament. Many of the NHL players who do play in the IIHF tournament come from teams eliminated before the playoffs or in the first round, and federations often hold open spots until the tournament to allow for players to join the tournament after their club team is eliminated. For many years, the tournament was an


title: "Ice hockey" content: amateur-only tournament, but this restriction was removed, beginning in 1977. The 1972 Summit Series and 1974 Summit Series, two series pitting the best Canadian and Soviet players without IIHF restrictions were major successes, and established a rivalry between Canada and the USSR. In the spirit of best-versus-best without restrictions on amateur or professional status, the series were followed by five Canada Cup tournaments, played in North America. Two NHL versus USSR series were also held: the 1979 Challenge Cup and Rendez-vous '87. The Canada Cup tournament later became the World Cup of Hockey, played in 1996, 2004 and 2016. The


title: "Ice hockey" content: United States won in 1996 and Canada won in 2004 and 2016. Since the initial women's world championships in 1990, there have been fifteen tournaments. Women's hockey has been played at the Olympics since 1998. The 2006 Winter Olympic final between Canada and Sweden marked the only time the women's world championship or Olympic final did not involve both Canada and the United States. Other ice hockey tournaments featuring national teams include the World U20 Championship, the World U18 Championships, the World U-17 Hockey Challenge, the World Junior A Challenge, the Ivan Hlinka Memorial Tournament, the World Women's U18 Championships


title: "Ice hockey" content: and the 4 Nations Cup. The annual Euro Hockey Tour, an unofficial European championship between the national men's teams of the Czech Republic, Finland, Russia and Sweden have been played since 1996–97. The Australian Ice Hockey League and New Zealand Ice Hockey League are represented by nine and five teams respectively. As of 2012, the two top teams of the previous season from each league compete in the Trans-Tasman Champions League. Ice hockey in Africa is a small but growing sport; while no African ice hockey playing nation has a domestic league, there are several regional leagues in South Africa.


title: "Ice hockey" content: Pond hockey is a form of ice hockey played generally as pick-up hockey on lakes, ponds and artificial outdoor rinks during the winter. Pond hockey is commonly referred to in hockey circles as shinny. Its rules differ from traditional hockey because there is no hitting and very little shooting, placing a greater emphasis on skating, puckhandling and passing abilities. Since 2002, the World Pond Hockey Championship has been played on Roulston Lake in Plaster Rock, New Brunswick, Canada. Since 2006, the US Pond Hockey Championships have been played in Minneapolis, Minnesota, and the Canadian National Pond Hockey Championships have been


title: "Ice hockey" content: played in Huntsville, Ontario. Ice hockey is the official winter sport of Canada. Ice hockey, partially because of its popularity as a major professional sport, has been a source of inspiration for numerous films, television episodes and songs in North American popular culture. The record for a Stanley Cup playoff game is 28,183, set on April 23, 1996, at the Thunderdome during a Tampa Bay Lightning – Philadelphia Flyers game. A record was set on December 11, 2010, when the University of Michigan's men's ice hockey team faced cross-state rival Michigan State in an event billed as "The Big Chill


title: "Ice hockey" content: at the Big House". The game was played at Michigan's (American) football venue, Michigan Stadium in Ann Arbor, with a capacity of 109,901 as of the 2010 football season. When UM stopped sales to the public on May 6, 2010, with plans to reserve remaining tickets for students, over 100,000 tickets had been sold for the event. Ultimately, a crowd announced by UM as 113,411, the largest in the stadium's history (including football), saw the homestanding Wolverines win 5–0. "Guinness World Records", using a count of ticketed fans who actually entered the stadium instead of UM's figure of tickets sold,


title: "Ice hockey" content: announced a final figure of 104,173. The record was approached but not broken at the 2014 NHL Winter Classic, which also held at Michigan Stadium, with the Detroit Red Wings as the home team and the Toronto Maple Leafs as the opposing team with an announced crowd of 105,491. Number of registered hockey players, including male, female and junior, provided by the respective countries' federations. Note that this list only includes the 42 of 76 IIHF member countries with more than 1,000 registered players as of October 2018. Ice hockey Ice hockey is a contact team sport played on ice,


title: Isotropy content: by the Poynting vector) in all directions. The gain of an arbitrary antenna is usually reported in decibels relative to an isotropic antenna, and is expressed as dBi or dB(i). Isotropy Isotropy is uniformity in all orientations; it is derived from the Greek "isos" (ἴσος, "equal") and "tropos" (τρόπος, "way"). Precise definitions depend on the subject area. Exceptions, or inequalities, are frequently indicated by the prefix "an", hence "anisotropy". "Anisotropy" is also used to describe situations where properties vary systematically, dependent on direction. Isotropic radiation has the same intensity regardless of the direction of measurement, and an isotropic field exerts


title: "Ibn Battuta" content: way to the town of Sijilmasa on the northern edge of the Sahara in present-day Morocco. There he bought a number of camels and stayed for four months. He set out again with a caravan in February 1352 and after 25 days arrived at the dry salt lake bed of Taghaza with its salt mines. All of the local buildings were made from slabs of salt by the slaves of the Masufa tribe, who cut the salt in thick slabs for transport by camel. Taghaza was a commercial centre and awash with Malian gold, though Ibn Battuta did not form


title: "Genomic imprinting" content: nutrient transport. Studies in domestic livestock, such as dairy and beef cattle, have implicated imprinted genes (e.g. IGF2) in a range of economic traits, including dairy performance in Holstein-Friesian cattle. A similar imprinting phenomenon has also been described in flowering plants (angiosperms). During fertilisation of the egg cell, a second, separate fertilization event gives rise to the endosperm, an extraembryonic structure that nourishes the embryo in a manner analogous to the mammalian placenta. Unlike the embryo, the endosperm is often formed from the fusion of two maternal cells with a male gamete. This results in a triploid genome. The 2:1


title: Indigo content: Indigo Indigo is a deep and rich color close to the color wheel blue (a primary color in the RGB color space), as well as to some variants of ultramarine. It is traditionally regarded as a color in the visible spectrum, as well as one of the seven colors of the rainbow: the color between violet and blue; however, sources differ as to its actual position in the electromagnetic spectrum. The color indigo is named after the indigo dye derived from the plant "Indigofera tinctoria" and related species. The first known recorded use of indigo as a color name in


title: Indigo content: English was in 1289. Species of "Indigofera" were cultivated in East Asia, Egypt, India, and Peru in antiquity. The earliest direct evidence for the use of indigo dates to around 4000 BC and comes from Huaca Prieta, in contemporary Peru. Pliny the Elder mentions the Indus Valley Civilization as the source of the dye after which it was named. It was imported from there in small quantities via the Silk Road. The Ancient Greek term for the dye was ("Sindhi dye"), which, adopted to Latin as "indicum" and via Portuguese gave rise to the modern word "indigo". Spanish explorers discovered


title: Indigo content: an American species of indigo and began to cultivate the product in Guatemala. The English and French subsequently began to encourage indigo cultivation in their colonies in the West Indies. Blue dye can be made from two different types of plants: the indigo plant, which produces the best results, and from the woad plant "Isatis tinctoria", also known as pastel. For a long time woad was the main source of blue dye in Europe. Woad was replaced by true indigo as trade routes opened up, and both plant sources have now been largely replaced by synthetic dyes. The Early Modern


title: Indigo content: English word "indigo" referred to the dye, not to the color (hue) itself, and "indigo" is not traditionally part of the basic color-naming system. Modern sources place indigo in the electromagnetic spectrum between 420 and 450 nanometers, which lies on the short-wave side of color wheel (RGB) blue, towards (spectral) violet. However, the correspondence of this definition with colors of actual indigo dyes is disputed. Optical scientists Hardy and Perrin list indigo as between 445 and 464 nm wavelength, which occupies a spectrum segment from roughly the color wheel (RGB) blue extending to the long-wave side, towards azure. Isaac Newton


title: Indigo content: introduced indigo as one of the seven base colors of his work. In the mid-1660s, when Newton bought a pair of prisms at a fair near Cambridge, the East India Company had begun importing indigo dye into England, supplanting the homegrown woad as source of blue dye. In a pivotal experiment in the history of optics, the young Newton shone a narrow beam of sunlight through a prism to produce a rainbow-like band of colors on the wall. In describing this optical spectrum, Newton acknowledged that the spectrum had a continuum of colors, but named seven: "The originall or primary


title: Indigo content: colours are Red, yellow, Green, Blew, & a violet purple; together with Orang, Indico, & an indefinite varietie of intermediate gradations." He linked the seven prismatic colors to the seven notes of a western major scale, as shown in his color wheel, with orange and indigo as the semitones. Having decided upon seven colors, he asked a friend to repeatedly divide up the spectrum that was projected from the prism onto the wall: I desired a friend to draw with a pencil lines cross the image, or pillar of colours, where every one of the seven aforenamed colours was most


title: Indigo content: full and brisk, and also where he judged the truest confines of them to be, whilst I held the paper so, that the said image might fall within a certain compass marked on it. And this I did, partly because my own eyes are not very critical in distinguishing colours, partly because another, to whom I had not communicated my thoughts about this matter, could have nothing but his eyes to determine his fancy in making those marks. Indigo is therefore counted as one of the traditional colors of the rainbow, the order of which is given by the mnemonic


title: Indigo content: "Roy G. Biv". James Clerk Maxwell and Hermann von Helmholtz accepted indigo as an appropriate name for the color flanking violet in the spectrum. Later scientists conclude that Newton named the colors differently from current usage. According to Gary Waldman, "A careful reading of Newton's work indicates that the color he called indigo, we would normally call blue; his blue is then what we would name blue-green, cyan or light blue." If this is true, Newton's seven spectral colors would have been: Red: Orange: Yellow: Green: Blue: Indigo: Violet: The human eye does not readily differentiate hues in the wavelengths


title: Indigo content: between what we today call blue and violet. If this is where Newton meant indigo to lie, most individuals would have difficulty distinguishing indigo from its neighbors. According to Isaac Asimov, "It is customary to list indigo as a color lying between blue and violet, but it has never seemed to me that indigo is worth the dignity of being considered a separate color. To my eyes it seems merely deep blue." Modern color scientists typically divide the spectrum between violet and blue at about 450 nm, with no indigo. Like many other colors (orange, rose, and violet are the


title: Indigo content: best-known), indigo gets its name from an object in the natural world—the plant named indigo once used for dyeing cloth (see also Indigo dye). The color "electric indigo" is a bright and saturated color between the traditional indigo and violet. This is the brightest color indigo that can be approximated on a computer screen; it is a color located between the (primary) blue and the color violet of the RGB color wheel. The web color "blue violet" or "deep indigo" is a tone of indigo brighter than pigment indigo, but not as bright as electric indigo. The color "pigment indigo"


title: Indigo content: is equivalent to the web color indigo and approximates the color indigo that is usually reproduced in pigments and colored pencils. The color of indigo dye is a different color from either spectrum indigo or pigment indigo. This is the actual color of the dye. A vat full of this dye is a darker color, approximating the web color midnight blue. Below are displayed these four major tones of indigo. "Electric indigo" is brighter than the pigment indigo reproduced below. When plotted on the CIE chromaticity diagram, this color is at 435 nanometers, in the middle of the portion of


title: Indigo content: the spectrum traditionally considered indigo, i.e., between 450 and 420 nanometers. This color is only an approximation of spectral indigo, since actual spectral colors are outside the gamut of the sRGB color system. At right is displayed the web color "blue-violet", a color intermediate in brightness between electric indigo and pigment indigo. It is also known as "deep indigo". The color box at right displays the web color indigo, the color indigo as it would be reproduced by artists' paints as opposed to the brighter indigo above (electric indigo) that is possible to reproduce on a computer screen. Its hue


title: Indigo content: is closer to violet than to indigo dye for which the color is named. Pigment indigo can be obtained by mixing 55% pigment cyan with about 45% pigment magenta. Compare the subtractive colors to the additive colors in the two primary color charts in the article on primary colors to see the distinction between electric colors as reproducible from light on a computer screen (additive colors) and the pigment colors reproducible with pigments (subtractive colors); the additive colors are significantly brighter because they are produced from light instead of pigment. Web color indigo represents the way the color indigo was


title: Indigo content: always reproduced in pigments, paints, or colored pencils in the 1950s. By the 1970s, because of the advent of psychedelic art, artists became used to brighter pigments, and pigments called "bright indigo" or "bright blue-violet" that are the pigment equivalent of the electric indigo reproduced in the section above became available in artists' pigments and colored pencils. 'Tropical Indigo' is the color that is called "añil" in the "Guía de coloraciones" (Guide to colorations) by Rosa Gallego and Juan Carlos Sanz, a color dictionary published in 2005 that is widely popular in the Hispanophone realm. "Indigo dye" is a greenish


title: Indigo content: dark blue color. Literature Marina Warner's novel "Indigo" (1992) is a retelling of Shakespeare's "The Tempest" and features the production of indigo dye by Sycorax. The French Army adopted dark blue indigo at the time of the French Revolution, as a replacement for the white uniforms previously worn by the Royal infantry regiments. In 1806, Napoleon decided to restore the white coats because of shortages of indigo dye imposed by the British continental blockade. However, the greater practicability of the blue color led to its retention, and indigo remained the dominant color of French military coats until 1914. The spiritualist


title: Indigo content: applications use electric indigo, because the color is positioned between blue and violet on the spectrum. Indigo Indigo is a deep and rich color close to the color wheel blue (a primary color in the RGB color space), as well as to some variants of ultramarine. It is traditionally regarded as a color in the visible spectrum, as well as one of the seven colors of the rainbow: the color between violet and blue; however, sources differ as to its actual position in the electromagnetic spectrum. The color indigo is named after the indigo dye derived from the plant "Indigofera


title: "Ibizan Hound" content: Ibizan Hound The Ibizan Hound (, ) is a lean, agile dog of the hound family. There are two hair types of the breed: smooth and wire. The more commonly seen type is the smooth. Some consider there to be a third type, long, but the longhair is most likely a variation of the wire. The Ibizan Hound is an elegant and agile breed, with an athletic and attractive outline and a ground-covering springy trot. Though graceful in appearance, it has good bone girth and is a rugged/hardy breed. Its large upright ears - a hallmark of the breed -


title: "Ibizan Hound" content: are broad at the base and frame a long and elegant headpiece. The neck is long and lean. It has a unique front assembly with well laid-back shoulders and relatively straight upper arm. Coming in both smooth and wire-coated varieties, their coat is a combination of red and white with the nose, ears, eye rims, and pads of feet being a light tan color. Its eyes are a striking amber color and have an alert and intelligent expression. The Ibizan may range in height, depending on which Standard you follow, from and weigh from , males being larger than females.


title: "Ibizan Hound" content: The Ibizan Hound coat can also range from smooth to Wire. wire coats are to be hard and can range from 1-3 inches in length. Ibizan Hounds are intelligent, active, and engaging by nature. They rank 53rd in Stanley Coren's The Intelligence of Dogs, being of average working/obedience intelligence, but many Ibizan owners will enjoy recounting a multitude of examples of their problem-solving abilities. They are true "clowns" of the dog world, delighting in entertaining their people with their antics. Though somewhat independent and stubborn at times, they do take well to training if positive methods are used, but will


title: "Ibizan Hound" content: balk at punitive training methods. They are generally quiet, but will alarm bark if necessary, so they make good watch dogs. They are sensitive hounds, and very good around children and other dogs alike. They generally make good house dogs, but are active and athletic, therefore need a lot of daily exercise. They do not make good kennel dogs. Ibizan hounds are sweet, but they are very stubborn and independent. Ibizan Hounds are "escapologists": they are able to jump incredible heights from a standstill, so they need very tall fences. They also have been known to climb, and many can


title: "Ibizan Hound" content: escape from crates, open baby gates and even locks. They have a strong prey drive, therefore they cannot be trusted off leash unless in a safely enclosed area. Once off the leash, they might not come back for a long time. A hound that knows where its home is and the surrounding area will usually return unscathed. The Ibizan Hound is typical of the Hound Group in that it rarely suffers from hereditary illness. Minor health concerns for the breed include seizures and allergies; very rarely, one will see axonal dystrophy, cataract, retinal dysplasia and deafness in the breed. Ibizan


title: "Ibizan Hound" content: Hound owners should have their dogs' eyes tested by a veterinarian before breeding. CERF and BAER testing is recommended for the breed. Ibizan Hounds are sensitive to barbiturate anesthesia, and typically live between 12 and 14 years. This breed originates in the island of Eivissa and has been traditionally used in the Catalan-speaking areas of Spain, and France where it was known under the name of "le charnigue", to hunt rabbits and other small game. The Ibizan Hound is a fast dog that can hunt on all types of terrain, working by scent, sound and sight. Hunters run these dogs


title: "Ibizan Hound" content: in mostly female packs, with perhaps a male or two, as the female is considered the better hunter. Traditionally a farmer may have one dog and a very well off farmer two dogs to catch rabbits for food. However in the last twenty years it is seen as a sport where between five and fifteen dogs can be seen in the chase of one rabbit. The Ibizan Hound authority Miquel Rosselló has provided a detailed description of a working trial which characterises their typical hunting technique and action, strikingly illustrated with action photos by Charles Camberoque which demonstrate hunt behaviour


title: "Ibizan Hound" content: and typical hunt terrain. While local hunters will at times use one dog or a brace, and frequently packs of six to eight or as many as fifteen, the working trial requires an evaluation of one or two braces. A brace is called a "colla". The couples should be tested on at least two to five rabbits (not hares), without the use of any other hunting aid. An inspection and evaluation of the exterior, fitness, character and obedience of the dogs is recommended prior to the hunt. The trial is qualified as having 5 parts. The dogs should show: (1)


title: "Ibizan Hound" content: careful tracking and scenting of the rabbit, without being distracted in the least, 0-30 points; (2) correct signalling of the game, patient stand, strong jump into the air, obedience 0-10 points; (3) chase, giving tongue, speed, sureness, anticipation 0-30 points; (4) putting the game to cover at close quarters, listening, waiting, obedience, correct attack 0-10 point; and (5) good catch, or correct indication of the game’s location, retrieval, obedience 0-20 points. Individual dogs are expected to show a great degree of discipline, obedience and co-operation. They should be extremely agile, have good speed and a powerful vertical jump from a


title: "Ibizan Hound" content: stationary position in rough and often heavily covered ground. They should have excellent scent-tracking abilities, give tongue at the right time when approaching the game closely, and otherwise be silent so that they can locate the game by sound. The Ibizan Hound is similar in function and type to several breeds, such as the Pharaoh Hound, the Cirneco dell'Etna, the Portuguese Podengo, and the Podenco Canario. The Ibizan Hound is the largest of these breeds, classified by the Fédération Cynologique Internationale as primitive types. It is believed the Ibizan Hound evolves from the "tesem", the ancient Egyptian hunting dog. Representations


title: "Ibizan Hound" content: of this dog on the walls of ancient tombs show a striking similarity to the modern Ibizan Hound. These dogs would have been brought to the island of Eivissa by the Phoenicians, who founded settlements there as early as the 8th century BC. A recent DNA analysis found that the breed was formed recently from other breeds. A more recent article argues that continued trait selective breeding may be behind this lack of support. In the United States, the Ibizan Hound is frequently competed in lure coursing through the AKC and ASFA, and also competes in LGRA straight racing and


title: "Ibizan Hound" content: NOTRA oval track racing. Some parts of the country also use them for coursing live prey, generally jackrabbits. The Ibizan Hound breed is recognized by the Fédération Cynologique Internationale, Continental Kennel Club, American Kennel Club, United Kennel Club, Kennel Club of Great Britain, Canadian Kennel Club, National Kennel Club, New Zealand Kennel Club, Australian National Kennel Council, America's Pet Registry, and American Canine Registry. It was fully recognized by the American Kennel Club in 1979. According to journalist Norman Lewis, when an owner no longer wants to own one of these dogs (having too much of an appetite, for instance),


title: "Ibizan Hound" content: it is considered very bad luck to kill the dog. Instead, they release the dog on the other side of the island, so that someone else might 'adopt' the animal. Ibizan Hound The Ibizan Hound (, ) is a lean, agile dog of the hound family. There are two hair types of the breed: smooth and wire. The more commonly seen type is the smooth. Some consider there to be a third type, long, but the longhair is most likely a variation of the wire. The Ibizan Hound is an elegant and agile breed, with an athletic and attractive outline


title: "Irish Wolfhound" content: Irish Wolfhound The Irish Wolfhound (, ) is a breed of domestic dog ("Canis lupus familiaris"), specifically a very large sighthound from Ireland. The name originates from its purposewolf hunting with dogsrather than from its appearance. Originally developed from war hounds with the purpose of being a hunting or guard dog. The Irish Wolfhound can be an imposing sight due to their formidable size. The breed is very old; there are suggestions it may have been brought to Ireland as early as 7000 BC. These dogs are mentioned, as cú (variously translated as hound, Irish hound, war dog, wolf dog,


title: "Irish Wolfhound" content: etc.) in Irish laws and in Irish literature which dates from the 5th century or, in the case of the Sagas, from the old Irish period - AD 600-900. The word "Cú" often became an added prefix of respect on the names of warriors as well as kings denoting that they were worthy of the respect and loyalty of a Cú. Ancient artworks and writings have encouraged modern authors to imagine their existence as a breed by 273 BC. However, there is indication that large dogs may have existed even as early as 279 BC when the Tectosages and Tolistobogii


title: "Irish Wolfhound" content: Celts sacked Delphi. Survivors left accounts of the fierce Celts and the huge dogs who fought with them and at their side. They were mentioned by Julius Caesar in his treatise, The Gallic Wars, and by 391 AD, they were written about by Roman Consul, Quintus Aurelius Symmachus, who received seven of them, "canes Scotici", as a gift to be used for fighting lions and bears, in his words, "all Rome viewed (them) with wonder". Wolfhounds were bred as hunting dogs by the ancients, who called them "Cú Faoil". The Irish continued to breed them for this purpose, as well


title: "Irish Wolfhound" content: as to guard their homes and protect their stock. Cúchulain, a name which translates literally as "hound of Culain", gained his name when as a child, known then as Sétanta, when he slew the ferocious guard dog of Culain, forcing him to offer himself as a replacement. During the English Conquest of Ireland, only the nobility were allowed to own Irish Wolfhounds, the numbers permitted depending on position. They were much coveted and were frequently given as gifts to important personages and foreign nobles. Wolfhounds were the companions of the regal, and were housed themselves alongside them. King John of


title: "Irish Wolfhound" content: England, in about 1210 presented an Irish hound, Gelert, to Llewellyn, a prince of Wales. The poet The Hon William Robert Spencer Immortalized this hound in a poem. In his "History of Ireland" completed 1571, Edmund Champion gives a description of the hounds used for hunting the wolves on the Dublin and Wicklow mountains. He says: They (the Irish) are not without wolves and greyhounds to hunt them, bigger of bone and limb than a colt. Due to their popularity overseas many were exported to European royal houses leaving numbers in Ireland depleted. This led to a declaration by Oliver


title: "Irish Wolfhound" content: Cromwell himself being published in Kilkenny on 27 April 1652 to ensure that sufficient numbers remained to control the wolf population. References to the Irish Wolfhound in the 18th century tell of its great size, strength and greyhound shape as well as its scarcity. Writing in 1790, Bewick described it as the largest and most beautiful of the dog kind; about 36 inches high, generally of a white or cinnamon colour, somewhat like the Greyhound but more robust. He said that their aspect was mild, disposition peaceful, and strength so great that in combat the Mastiff or Bulldog was far


title: "Irish Wolfhound" content: from being an equal to them. The last wolf in Ireland is thought to have been killed at Myshall, on the slopes of Mount Leinster in Co. Carlow in 1786 by a pack of wolfdogs kept by a Mr Watson of Ballydarton. The remaining hounds in the hands of a few families who were mainly descendants of the old Irish chieftains, were now symbols of status rather than hunters, they were said to be the last of their race. Scotsman Captain George Augustus Graham is responsible with a few other breeders for attempting to reaffirm the breed's existence. In 1879


title: "Irish Wolfhound" content: he wrote: "It has been ascertained beyond all question that there are few specimens of the breed still left in Ireland and England to be considered Irish Wolfhounds, though falling short of the requisite dimensions. This blood is now in my possession." Captain Graham devoted his life to ensuring the survival of the Irish Wolfhound. Owing to the small numbers of surviving specimens outcrossing was used in the breeding programme. It is believed that Borzoi, Great Dane, Scottish Deerhound and English Mastiff dogs all played their part in Graham's creation of the dog we currently know. The famous English Mastiff


title: "Irish Wolfhound" content: Garnier's Lion was bred to the Deerhound Lufra, and their offspring Marquis enters Wolfhound pedigrees through his granddaughter Young Donagh. Graham included "a single outcross of Tibetan Wolf Dog". This was long assumed to have been a Tibetan Mastiff. However, a photograph of "Wolf" shows a bearded, long-coated dog—what would now be called a "Tibetan Kyi Apso" or "dokhyi apso". In 1885 Captain Graham with other breeders founded the Irish Wolfhound Club, and the Breed Standard of Points to establish and agree the ideal to which breeders should aspire. The Wolfhound was historically a dog that only nobles could own


title: "Irish Wolfhound" content: and was taken up by the British during their rule in Ireland. This made it unpopular as a national symbol and the Kerry Blue Terrier was adopted by Republicans such as Michael Collins.The Wolfhound has been adopted as a symbol by both rugby codes. The national rugby league team is nicknamed the Wolfhounds, and the Irish Rugby Football Union, which governs rugby union, changed the name of the country's A (second-level) national team in that code to the Ireland Wolfhounds in 2010. Considered by the American Kennel Club to be the tallest of all dog breeds, describing the breed as,


title: "Irish Wolfhound" content: "Of great size and commanding appearance, the Irish Wolfhound is remarkable in combining power and swiftness with keen sight. The largest and tallest of the galloping hounds, in general type he is a rough-coated, Greyhound-like breed; very muscular, strong though gracefully built; movements easy and active; head and neck carried high, the tail carried with an upward sweep with a slight curve towards the extremity". The average height of an Irish Wolfhound should be taller than that of a Great Dane. However, the wolfhound is not to be confused with being the heaviest, as its structure should be similar to


title: "Irish Wolfhound" content: that of a Greyhound, with a very broad and deep chest that tucks up. Its colour may be grey, brindle, red, black, white, fawn, and wheaten. The Irish Wolfhound was bred for long solitary hunts based solely on the dog's ability to visualize its landscape and perceive, unlike scent hounds (such as Bloodhounds and Beagles) who rely on scent rather than sight. For this reason, the neck of an Irish Wolfhound should be long with the head held high the majority of the time. The Irish Wolfhound should also appear to be longer than it is tall. Once used to


title: "Irish Wolfhound" content: hunt wolves, an Irish Wolfhound’s structure should appear as if it is “fast enough to catch a wolf, and strong enough to kill it”. The AKC specifies the minimum height as for mature males, for females; the minimum weight: for males, for females. It is not rare to see modern day female hounds reaching the minimal height requirements of those of male hounds; most females are well over and in most AKC conformation shows a wolfhound’s height is looked at with as much importance as the hound’s head and face structure. Per the AKC, great size, including height of shoulder


title: "Irish Wolfhound" content: and proportionate length of body is to be aimed at, to firmly establish a breed averaging in males. The height/weight standards in Ireland and England are slightly different: males /, females /. Irish Wolfhounds have a varied range of personalities and are most often noted for their personal quirks and individualism. An Irish Wolfhound, however, is rarely mindless, and despite its large size is rarely found to be destructive in the house or boisterous. This is because the breed is generally introverted, intelligent, and reserved in character. An easygoing animal, the Irish Wolfhound is quiet by nature. Wolfhounds often create


title: "Irish Wolfhound" content: a strong bond with their family and can become quite destructive or morose if left alone for long periods of time. An Irish Wolfhound is not a guard dog and will protect individuals rather than the house or the owner’s possessions. However independent the wolfhound is, the breed becomes attached to both owners and other dogs they are raised with and is therefore not the most adaptable of breeds. Bred for independence, an Irish Wolfhound is not necessarily keen on defending spaces. A wolfhound is most easily described by its historical motto, “gentle when stroked, fierce when provoked”. They should


title: "Irish Wolfhound" content: not be territorially aggressive to other domestic dogs but are born with specialized skills and it is common for hounds at play to course another dog. This is a specific hunting behavior, not a fighting or territorial domination behavior. Most Wolfhounds are very gentle with children. The Irish Wolfhound is relatively easy to train. They respond well to firm, but gentle, consistent leadership. However, historically these dogs were required to work at great distances from their masters and think independently when hunting rather than waiting for detailed commands and this can still be seen in the breed. The Wolfhound of


title: "Irish Wolfhound" content: today is far from the one that struck fear into the hearts of the Ancient Romans. Irish Wolfhounds are often favored for their loyalty, affection, patience and devotion. Although at some points in history they have been used as watchdogs, unlike some breeds, the Irish Wolfhound is usually unreliable in this role as they are often friendly toward strangers, although their size can be a natural deterrent. However, when protection is required this dog is never found wanting. When they or their family are in any perceived danger they display a fearless nature. Author and Irish Wolfhound breeder Linda Glover


title: "Irish Wolfhound" content: believes the dogs' close affinity with humans makes them acutely aware and sensitive to ill will or malicious intentions leading to their excelling as a guardian rather than guard dog. Like many large dog breeds, Irish Wolfhounds have a relatively short lifespan. Published lifespan estimations vary between 6 and 10 years with 7 years being the average. Dilated cardiomyopathy and bone cancer are the leading cause of death and like all deep-chested dogs, gastric torsion (bloat) is common; the breed is affected by hereditary intrahepatic portosystemic shunt. In a privately funded study conducted under the auspices of the Irish Wolfhound


title: "Irish Wolfhound" content: Club of America and based on an owner survey, Irish Wolfhounds in the United States from 1966 to 1986 lived to a mean age of 6.47 and died most frequently of bone cancer. A more recent study by the UK Kennel Club puts the average age of death at 7 years. Studies have shown that neutering is associated with a higher risk of bone cancer in various breeds, with one study suggesting that castration of male Irish Wolfhounds should be avoided at least until the dog is fully grown. Irish Wolfhounds should not receive additional supplements when a good dog


title: "Irish Wolfhound" content: food is used. It is generally accepted that they should be fed a low protein adult dog food (19 to 21% protein) from puppyhood onward. Most breeders today recommend that they not be supplemented to slow their rapid growth. Irish Wolfhounds are the tallest of all dog breeds, sometimes reaching 7 feet tall on their hind legs. They are well suited to rural life, but their medium energy profile allows them to adjust fairly well to suburban and urban life as well, provided they receive appropriate exercise. Genetically, the Irish Wolfhound as a breed is threatened by a bottleneck related


title: "Irish Wolfhound" content: to the over-use of a popular sire. Irish Wolfhound The Irish Wolfhound (, ) is a breed of domestic dog ("Canis lupus familiaris"), specifically a very large sighthound from Ireland. The name originates from its purposewolf hunting with dogsrather than from its appearance. Originally developed from war hounds with the purpose of being a hunting or guard dog. The Irish Wolfhound can be an imposing sight due to their formidable size. The breed is very old; there are suggestions it may have been brought to Ireland as early as 7000 BC. These dogs are mentioned, as cú (variously translated as


title: "Integrated circuit" content: Integrated circuit An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, normally silicon. The integration of large numbers of tiny transistors into a small chip results in circuits that are orders of magnitude smaller, cheaper, and faster than those constructed of discrete electronic components. The IC's mass production capability, reliability and building-block approach to circuit design has ensured the rapid adoption of standardized ICs in place of designs using discrete transistors. ICs are now used


title: "Integrated circuit" content: in virtually all electronic equipment and have revolutionized the world of electronics. Computers, mobile phones, and other digital home appliances are now inextricable parts of the structure of modern societies, made possible by the small size and low cost of ICs. Integrated circuits were made practical by mid-20th-century technology advancements in semiconductor device fabrication. Since their origins in the 1960s, the size, speed, and capacity of chips have progressed enormously, driven by technical advances that fit more and more transistors on chips of the same size – a modern chip may have many billions of transistors in an area the


title: "Integrated circuit" content: size of a human fingernail. These advances, roughly following Moore's law, make computer chips of today possess millions of times the capacity and thousands of times the speed of the computer chips of the early 1970s. ICs have two main advantages over discrete circuits: cost and performance. Cost is low because the chips, with all their components, are printed as a unit by photolithography rather than being constructed one transistor at a time. Furthermore, packaged ICs use much less material than discrete circuits. Performance is high because the IC's components switch quickly and consume comparatively little power because of their


title: "Integrated circuit" content: small size and close proximity. The main disadvantage of ICs is the high cost to design them and fabricate the required photomasks. This high initial cost means ICs are only practical when high production volumes are anticipated. An "integrated circuit" is defined as: A circuit in which all or some of the circuit elements are inseparably associated and electrically interconnected so that it is considered to be indivisible for the purposes of construction and commerce. Circuits meeting this definition can be constructed using many different technologies, including thin-film transistors, thick-film technologies, or hybrid integrated circuits. However, in general usage "integrated


title: "Integrated circuit" content: circuit" has come to refer to the single-piece circuit construction originally known as a "monolithic integrated circuit". Arguably, the first examples of integrated circuits would include the Loewe 3NF. Although far from a monolithic construction, it certainly meets the definition given above. Early developments of the integrated circuit go back to 1949, when German engineer Werner Jacobi (Siemens AG) filed a patent for an integrated-circuit-like semiconductor amplifying device showing five transistors on a common substrate in a 3-stage amplifier arrangement. Jacobi disclosed small and cheap hearing aids as typical industrial applications of his patent. An immediate commercial use of his


title: "Integrated circuit" content: patent has not been reported. The idea of the integrated circuit was conceived by Geoffrey Dummer (1909–2002), a radar scientist working for the Royal Radar Establishment of the British Ministry of Defence. Dummer presented the idea to the public at the Symposium on Progress in Quality Electronic Components in Washington, D.C. on 7 May 1952. He gave many symposia publicly to propagate his ideas and unsuccessfully attempted to build such a circuit in 1956. A precursor idea to the IC was to create small ceramic squares (wafers), each containing a single miniaturized component. Components could then be integrated and wired


title: "Integrated circuit" content: into a bidimensional or tridimensional compact grid. This idea, which seemed very promising in 1957, was proposed to the US Army by Jack Kilby and led to the short-lived Micromodule Program (similar to 1951's Project Tinkertoy). However, as the project was gaining momentum, Kilby came up with a new, revolutionary design: the IC. Newly employed by Texas Instruments, Kilby recorded his initial ideas concerning the integrated circuit in July 1958, successfully demonstrating the first working integrated example on 12 September 1958. In his patent application of 6 February 1959, Kilby described his new device as "a body of semiconductor material


title: "Integrated circuit" content: … wherein all the components of the electronic circuit are completely integrated." The first customer for the new invention was the US Air Force. Kilby won the 2000 Nobel Prize in Physics for his part in the invention of the integrated circuit. His work was named an IEEE Milestone in 2009. Half a year after Kilby, Robert Noyce at Fairchild Semiconductor developed a new variety of integrated circuit, more practical than Kilby's implementation. Noyce's design was made of silicon, whereas Kilby's chip was made of germanium. Noyce credited Kurt Lehovec of Sprague Electric for the principle of p–n junction isolation,


title: "Integrated circuit" content: a key concept behind the IC. This isolation allows each transistor to operate independently despite being part of the same piece of silicon. Fairchild Semiconductor was also home of the first silicon-gate IC technology with self-aligned gates, the basis of all modern CMOS integrated circuits. The technology was developed by Italian physicist Federico Faggin in 1968. In 1970, he joined Intel in order to develop the first single-chip central processing unit (CPU) microprocessor, the Intel 4004, for which he received the National Medal of Technology and Innovation in 2010. The 4004 was designed by Busicom's Masatoshi Shima and Intel's Ted


title: "Integrated circuit" content: Hoff in 1969, but it was Faggin's improved design in 1970 that made it a reality. Advances in IC technology, primarily smaller features and larger chips, have allowed the number of transistors in an integrated circuit to double every two years, a trend known as Moore's law. This increased capacity has been used to decrease cost and increase functionality. In general, as the feature size shrinks, almost every aspect of an IC's operation improves. The cost per transistor and the switching power consumption per transistor goes down, while the memory capacity and speed go up, through the relationships defined by