The Interborough Rapid Transit Company (IRT) was the first subway system in New York City, opening in 1904. It was created to provide efficient transportation for the growing population and connected key areas of Manhattan. The IRT initially operated a single line, which has since expanded into a larger network. In 1940, the IRT was consolidated with other transit systems, becoming part of the New York City Transit Authority. Today, the IRT operates several subway lines, including the 1, 2, 3, 4, 5, and 6 trains, continuing to serve millions of passengers each day.