What is List of unused or defunct New York City Subway services?
The [[Metropolitan Transportation Authority]] (MTA) does not use some letters and numbers to identify routes on the [[New York City Subway]]. == Unused letters == * {{NYCS symbol|I|50px}}: the letter '''I''' could be confused with [[IRT Broadway - Seventh Avenue Line|Line 1]]. * {{NYCS symbol|O|50px}}: the letter '''O''' could be confused with the number '''0''', which the MTA uses to help their computers recognize the [[42nd Street Shuttle]]. * {{NYCS symbol|P|50px}}: the letter '''P''' could sound funny or rude, because it sounds like the word “pee”. * {{NYCS symbol|U|50px}}: the letter '''U''' could be confused with with the word “you”. * {{NYCS symbol|Y|50px}}: the letter '''Y''' could be confused with with the word “why”. == Internal numbers and letters == The MTA privately (or internally) uses the number '''0''' and the letter '''H''', to help their computers recognize the three separate shuttles. The three shuttles use the letter '''S''' on maps and posters, and this can confuse computers. * {{NYCS symbol|0|50px}}: The number '''0''' represents the [[42nd Street Shuttle]]. * {{NYCS symbol|H|50px}}: The letter '''H''' represents the [[Rockaway Park Shuttle]]. The last time that the MTA used the letter H on maps and posters was in 2012, because the damage from [[Hurricane Sandy]] prevented the MTA from running [[IND Eighth Avenue Line|Line A]]. == Reserved letters == The MTA reserves the letters '''T''' and '''X''' to identify the services that they want to build or run in the future. * {{NYCS symbol|T|50px}}: the letter '''T''' represents a service that the MTA plans to run, when they finish building the [[Second Avenue Subway]]. * {{NYCS symbol|X|50px}}: the letter '''X''' represents a service that the MTA plans to run in the future, but have not decided on what number or letter to use. == Defunct letters and numbers == * {{NYCS symbol|8H|50px}}: the number '''8''' used to represent trains that ran on the [[IRT Third Avenue Line]]. Line 8 stopped running on April 28, 1973, when the MTA closed th