Writing on walls is not a modern phenomenon.
Our distant ancestors etched depictions of wildlife and hunting scenes on the insides of caves. Historians speculate that their aim was to placate the gods before the often perilous and sometimes futile task of gathering food.
There are known expressions of social and political unrest that date back to Greek and Roman civilizations. Some historians even believe that wall writing was used to advertise public services, inns, baths and even brothels -- a precursor to the modern billboard.
Today, in the graffiti-inundated Argentine capitol of Buenos Aires, as in most of the world's largest cities, the activities of graffiti writers, which some historians say has roots in cave art, is thriving.
Grafitti Tours in Argentina
A vibrant and expressive scene exists in Buenos Aires, where advocates argue there is a higher proportion of quality work than cheap graffiti tagging. In any event, it is almost impossible to avoid the visual melee that adorns practically every grey, derelict wall in the city.
A pair of enthusiasts from Britain have created a central hub to advocate for the variety and quality of this work, called Graffitimundo, an online resource connecting the art to its artists.
They also provide an alternative and informed tour around Buenos Aires and its urban art scene. Instead of a tour of the Recoleta Cemetery or watching a game of polo, tourists can get up close and personal with the very best street art, seeing the work (sometimes as it is being made) and meeting the artists responsible.
Co-founder Marina Charles attributes the level of quality and expression to a backlash against difficult economic times in the early 2000s.
"After 2001, there was a sense of creating a social experiment on the streets," Charles said. "Groups of artists all felt they could come out on to the streets and bring something positive to the environment they were living in."
In fact, the street art advocates claim a lack of police interest in graffiti and the public's tolerance of it has given local artists the time and psychological freedom to paint uninterrupted and unafraid of retribution.
That notion is disputed by many in Buenos Aires. The mayor, Mauricio Macri said during his campaign that anti-graffiti efforts should be part of any plan to help clean up the city, but since his election in 2007, no major initiatives have been undertaken.
There are no specific laws banning graffiti in the capitol, unless it is contains ethnic or racial slurs, ABC News producer Joe Goldman in Buenos Aires reported.
"One could paint a wall of a police station without having any problem in Buenos Aires," Goldman added.
Indeed, Marton Otonelo, a spokesman for the Argentine Director General's Office in Buenos Aires, told ABC News, "There are two types of street art: political and artistic. Both are good. They are part of the city. ... Street art doesn't bother us."
There are even now local businesses who employ the artists to adorn their shop fronts.
A rumor persists about a local politician, dogged by political graffiti, who employed the services of one of the more respected local artists to paint the front of his house. Such is the respect that artists have for each other's work, it has even acted as an effective deterrent against further vandalism.
Grafitti's Origins and Modern History
The beginnings of the graffiti and street art movement have been traced to the mid- to late-1960s in New York City, although there is evidence that it may have begun in Philadelphia at about the same time. Urban historians say the movement emerged from two factions -- political activists looking for a forum and street gangs staking territory.
The word graffiti comes from the Italian graffiato, which means scratched. It refers to work that is written, using words or symbols, and as a result, grafitti artists often are referred to as "writers."
Throughout its recent history, there have been strong arguments that graffiti is simply vandalism, an unwanted sullying of walls and public places; urban visual noise, at best.
The most common form, and the most reviled, is known as "tagging." A writer quickly scrawls his name, or moniker, on whatever outdoor, or publicly visible surface he can find, avoiding detection by the authorities in the process -- a quick-in, quick-out blitzkrieg of bus shelters, railway stations and billboards, leaving little time for artistic expression.
One particular individual known as Tox has been tagging on London's transport network for over nine years, usually eluding the London Transport Police and causing hundreds of thousands of pounds worth of damage, much to the frustration of London underground employees, such as Andy Hogg.
"Anyone that commutes on our trains quite regularly, I think, will have seen 'Tox,'" Hogg said on a Sky Travel documentary viewable on YouTube. "I don't know anywhere where I haven't seen a Tox tag -- on the walls, in the trains, in places even I can't access."
Perhaps the most famous renegade graffiti artist and "enemy of the state" to come out of London is the stencil artist Banksy, who, in earlier years, was pursued, unsuccessfully, by the police. He has now, however, become one of the most celebrated graffiti artists in the world -- with particularly iconic works, such as one depicting two police officers kissing. His pieces now sell for hundreds of thousands of dollars, although his identity still remains something of a mystery.
The Sinister Side of Graffiti Art
Tox is probably destined for lesser things. But while he may be thought of as a nuisance and a vandal, in extreme cases, tagging elsewhere in the world carries even more sinister connotations.
In Sao Paolo, Brazil, gangs have developed their own system of glyphs, a unique written language born from a lack of literacy that they use to provoke their rivals. Writing in territory that isn't theirs or writing over glyphs of a rival gang carries a de facto death penalty.
Young gang members with nothing to lose and a lot to prove take absurd risks to tag in the most inaccessible of places to bring further notoriety to themselves and their crews. There have been reports of some dying in the process, falling several stories while attempting to tag the highest levels of high-rise apartment blocks.
Will the Recession Bring More Graffiti to Our Streets?
Unlike Sao Paolo's grafitti writers, proponents claim Buenos Aires' artists generally remain unconnected to gangs and criminal activities. Still, their origins may lay in troubled times.
Argentina's massive economic crash in the late 1990s created such widespread social and economic difficulties in the country that authorities had far too much on their plate to be chasing vandals. Out of the ashes of the Argentine economy, individuals and "crews" such as "Doma" and stencilists "Run Don't Walk" emerged to revitalize their streets.
One local street artist, known as Jaz, feels a distinct difference between the attitudes of the Argentine scene as compared to other parts of the world.
"Here in Buenos Aires, it's not like other cities,"Jaz said. "It's not a competition with other graffiti writers. When I paint in France, I feel, 'If you paint in this place, you're not welcome. If you paint in that place, you're not welcome.' Here, you paint, and you've got a piece for years in the street."
Such is the liberal attitude in the city that artists come specifically from other parts of the world just to paint in Buenos Aires. The Italian artist known as Blu recently completed an incredibly ambitious (or as he calls it, ambiguous) animated work, painted in the streets of Buenos Aires and Baden, Switzerland, using stop-motion filming techniques.
If the liberal example set by the people of Buenos Aires is an indication of future attitudes toward graffiti, then we might expect to see more graffiti in our streets amid growing economic gloom.
And, if we're lucky, at least the quality might be good.
ABC News' Joe Goldman in Buenos Aires and Gabriel O'Rorke in London contribute to this report