The Chicago White Sox are an American professional baseball team based in Chicago. The White Sox compete in Major League Baseball (MLB) as a member club of the American League (AL) Central Division. The team is owned by Jerry Reinsdorf, and plays its home games at Guaranteed Rate Field, located on Chicago's South Side. They are one of two MLB teams based in Chicago, alongside the National League (NL)’s Chicago Cubs.

Major League Baseball (MLB) is a professional baseball league and the highest level of organized baseball in the United States and Canada. One of the big four major leagues, MLB comprises 30 teams, divided equally between the National League (NL) and the American League (AL), with 29 in the United States and 1 in Canada. Formed in 1876 and 1901, respectively, the NL and AL cemented their cooperation with the National Agreement in 1903, making MLB the oldest major professional sports league in the world. They 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.