In New York City, the massive underground rail system is officially known as the New York City Subway, and the individual vehicles are simply called subway trains. Unlike London, where the system is colloquially known as "The Tube," or Washington D.C., where it is called "The Metro," New Yorkers almost exclusively use the term "Subway." You might also hear residents refer to specific lines by their letter or number—such as "taking the L" or "hopping on the 4 train." Historically, the system was a collection of private companies (the IRT, BMT, and IND), and while those names are mostly gone, they still dictate the "A Division" (numbered) and "B Division" (lettered) sizing of the cars. In 2026, the MTA (Metropolitan Transportation Authority) manages the entire network. While "the train" is the most common casual shorthand, "Subway" remains the definitive identifier. Interestingly, while most of the system is underground, about 40% of the tracks are actually elevated or at grade, yet the name "Subway" is applied universally to the entire 665-mile network.