4. Car types and details

The NYC subway uses two sizes of cars - the A division, listed above, uses thinner cars that have three sets of doors on each side, used in chains of up to 14; the B division, listed above, uses thicker cars that have four sets of doors on each side, in chains of up to 10.

Trains are marked by the service label in either black or white (for appropriate contrast) on a field in the color of its mainline. The field is enclosed in a circle for most services, or a diamond for special services, such as rush-hour only expresses on a route that ordinarily runs local. Rollsigns also typically include the service names and terminals. When the R44 and R46 cars were rebuilt the rollsigns on the side of the cars were replaced with electronic LCD signs while the front service sign remained as a rollsign, while the rebuilt R32 cars had rollsigns on the sides, but a digital light display in the front. All cars built since 1992, including the R110A, R110B, R142, R142A, R143, R160A, and R160B are equipped with digital signs on the front, sides, and interior (except for the R110B, which has rollsigns on the front).

These newer cars also feature recorded announcements for door closings, stations, and other general messages in lieu of conductor announcements, although live conductor announcements can still be made. The recordings began in the late 1990s and featured Bloomberg Radio on-air personalities, who volunteered at the request of their employer and future city mayor Michael Bloomberg. Voices include Jessica Gottesman (now at 1010 WINS radio), Charlie Pellett, and Catherine Cowdery. With regards to why certain messages are voiced by males and others by females, MTA spokesperson Gene Sansone said in 2006 that, "Most of the orders are given by a male voice, while informational messages come from females. Even though this happened by accident, it is a lucky thing because a lot of psychologists agree that people are more receptive to orders from men and information from women"