Major League Baseball (MLB) is a professional baseball organization and the oldest major professional sports league in the world. As of 2022, a total of 30 teams play in Major League Baseball, 15 teams in the National League (NL) and 15 in the American League (AL), with 29 in the United States and 1 in Canada. The NL and AL were formed in 1876 and 1901, respectively. Beginning in 1903, the two leagues signed the National Agreement and cooperated but remained legally separate entities until 2000, when they merged into a single organization led by the Commissioner of Baseball. MLB is headquartered in Midtown Manhattan.