The New York City Subway is one of the largest and busiest subway systems in the world, serving millions of passengers daily. It operates 24 hours a day, providing essential connectivity across the five boroughs of New York City. With its extensive network of over 400 kilometers of track and 472 stations, it plays a crucial role in the city's public transportation infrastructure. Established in 1904, the subway has undergone numerous expansions and renovations, adapting to the growing needs of the city. It features a diverse range of train lines, each identified by a letter or number, making it easier for commuters to navigate the system efficiently.