The "G line" refers to a specific route in the New York City Subway system, primarily serving the borough of Brooklyn. It runs between Church Avenue and Court Square, connecting various neighborhoods and providing access to other subway lines. The G line is unique as it does not connect to the Manhattan subway system, making it a vital link for local commuters. The G line operates on a mix of elevated and underground tracks, with several key stops including Greenpoint, Williamsburg, and Fort Greene. It is known for its frequent service and is an essential transportation option for residents and visitors in the areas it serves.