The New York City Subway runs 24 hours, seven days a week. However, riders should consider that services significantly change between midnight and 06:00 am. When traveling during these hours, passengers are recommended to print out the late-night subway service map or download it digitally. Therefore even though the subway operates 24 hours a day, not all lines operate at all times.



In the NYC Subway terminology, a "line" means the physical trackage used by trains that are used by lettered or numbered services. Currently, the company or division names are not used publicly, when the line names may be used occasionally. The services that are running on certain lines tend to change periodically, but the lines refer to static trackage. Therefore the line represents the physical structure of tracks that trains run over. Every section of the system is assigned with a unique name that necessarily starts with its first division (IND, IRT, or BMT). For example, the line that runs under Eighth Avenue is called the IND Eighth Avenue Line. During the time, some lines have changed their names and divisions, but this happened relatively rarely. Service in the subway terminology refers to the route which the train takes across the various lines. A service can operate along various lines and even different divisions. For example, the R service is running along the IND Queens Boulevard Line. Currently, the New York City Subway includes 36 different rail lines. The 63rd Street Lines and the Archer Avenue Lines are both classified as two separate lines because of their structure. Both lines are available to serve two divisions on distinct sections of track. Each line has a specific color and name. For example, the 8th Avenue line is always blue when Broadway 7th Avenue is always red. Due to the number of lines, even locals frequently don't know the official name of the line. However, even though it migh