The National Basketball Association is a professional basketball league in North America. The league is composed of 30 teams and is one of the major professional sports leagues in the United States and Canada. It is the premier men’s professional basketball league in the world.The NBA was founded on June 6, 1946, as the Basketball Association of America (BAA). The league adopted the name National Basketball Association on August 3, 1949, after merging with the rival National Basketball League (NBL). The league’s several international as well as individual team offices are directed out of its head offices located in the Olympic Tower at 645 Fifth Avenue in New York City.