Trains range from ultra-luxurious to very plain-jane commuter trains. Most people ride the train because its gets them between cities, or to and from cities, without having to deal with either vehicle traffic or airport hassles. Another reason that people take trains is that they are usually cheaper than taking planes. In addition, trains usually have bigger seats than and more space to move around in than either airplanes or buses. Trains travel on their own tracks, so you can get from city center to city center without having to worry about highway traffic. Cars, buses and airplanes all require some use of highways - usually some of the most congested. Many railroad stations are located within walking distance of city centers. Trains can carry more people, more efficiently and with a lower environmental cost than almost any other form of transportation. Trains are very good for serving densely populated urban areas and their suburbs. If you consider rail-based mass transit to be trains, then trains are very good at serving inner city areas and densely populated suburbs with closely-spaced stops and frequent service. Trains are very safe, on a per-mile-traveled basis. Safer than cars or buses, not as safe as airplanes. A few trains, such as those that cross the U.S., Canada, the Alps of Europe and Russia offer extremely beautiful scenery. Some of the newest trains offer super-fast electrified service. They can get you between cities faster than any other mode of transportation (if you include the time spent in getting to and from airports). Usually people who commute from long distances find that traveling by train is the most cost-effective and most productive way to get to and from homes to their workplace.
The negatives of trains is that they do not run everywhere, and in many areas they don't run very often. Trains can be subject to delays just like planes and buses. Trains are not always maintained in good condition so that riding them is not very pleasant. The nicest trains cost a lot more money to ride than run-of-the-mill commuter trains. Many trains offer almost no scenic views. They run in ditches, tunnels and past messy backyards. The majority of trains travel slower than most cars on highways. This is because they run on tracks that are not built for high-speed, they have frequent stops, use older diesel technology and are not maintained in top condition. In addition, they may run on tracks that are so busy that they have railroad traffic jams that slow everything down.