The National Basketball Association (NBA) is a professional basketball league, composed of thirty teams in North America (twenty-nine in the United States and one in Canada). It is an active member of USA Basketball (USAB), which is recognized by the International Basketball Federation as the National Governing Body (NGB) for basketball in the United States. The NBA is one of the four major North American professional sports leagues, which include Major League Baseball (MLB), the National Football League (NFL), and the National Hockey League (NHL). The league was founded in New York City on June 6, 1946 as the Basketball Association of America (BAA). The league adopted the name National Basketball Association in 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. NBA Entertainment and NBA TV studios are directed out of offices located in Secaucus, New Jersey.