T Boston, commonly known as the MBTA or the "T," is the public transportation system serving the Greater Boston area. It includes subway, bus, commuter rail, and ferry services, making it a vital part of daily life for residents and visitors. The subway system has four main lines, identified by colors: Red, Orange, Blue, and Green. The T is operated by the Massachusetts Bay Transportation Authority and provides an affordable and efficient way to navigate the city and surrounding suburbs. It connects key areas, including downtown Boston, Cambridge, and Brookline, facilitating access to work, education, and entertainment.