List of World Series champions
The World Series is the annual championship series of Major League Baseball (MLB) and concludes the MLB postseason. First played in 1903, the World Series championship is determined through a best-of-seven playoff and is a contest between the champions of baseball's National League (NL) and American League (AL). Often referred to as the "Fall Classic", the modern World Series has been played every year since 1903 with two exceptions: in 1904, when the NL champion New York Giants declined to play the AL champion Boston Americans; and in 1994, when the series was canceled due to the players' strike.
Major professional sports leagues in the United States and Canada
Usage of the phrase in baseball started with organization of championship series between the National League and the earlier American Association in the 1880s, later to be known as the World Series. Major League Baseball later set up the World Baseball Classic, a quadrennial international competition, in an effort to crown a true world champion. By the 1950s, the phrase "World Champions" was also being used by the newly formed NBA. The Super Bowl, the interleague championship between the NFL and American Football League, was explicitly named a "World Championship Game" for its first iteration.