New Yorkers claim the New York City Subway System (In America, they call the "Underground" the "Subway". It's probably for the same reason that they leave the "u" out of words like colour and favour.) as the oldest underground in the world. This perhaps, explains why is it inconsistent, complicated, and in desperate need of repair.

Trains are numbered from 1-9 and then A-Z (mysteriously missing, however, are trains 8, X, or Y). They are also coded by color. Thus, the 1, 2, 3, and 9 are red, the 4, 5, and 6 are green, the 7 is purple, the A, C, E, and S are blue, and so on. It is easy to remember the color combinations because trains of the same color run on the same tracks, except when they don't. An unintelligible voice will announce this when this happens. Most trains have their number or letter in a little circle, some have a square or a diamond shape instead. This is to confuse you. Avoid the green trains during rush hour. Trust me.

Some trains are express trains and only stop at big stations. Some trains are local trains and stop at every station, except for the local trains that skip stations on odd Thursdays on a full moon. All of these exceptions are posted on handy signs in the station. Somewhere.

If you get confused, don't worry. All of the large stations have thoughtfully provided homeless persons who can direct you for a nominal fee. At the World Trade Center, the homeless person by the A,C, and E trains also gives a very informative lecture on the history of the subway system.