Major League Baseball (MLB) refers to a North American professional baseball organization formed from two major professional baseballs leagues, the National League and the American League. Each leagues is broken into three divisions: East, Central and West. The leagues have slightly different rules. Each team plays 162 games annually in the regular season that runs from early April to the last week in September. Post season playoffs culminate in the World Series, in which the champion of each league playing in a best-of-seven-games series.

1. Major League Baseball Executives
2. Mitchell's Steroid Report

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