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.
2000s (decade)
The New York Yankees won the first Major League Baseball World Series of the decade in 2000, as well as the last World Series of the decade in 2009. The Boston Red Sox won their first World Series since 1918 in 2004 and then again in 2007.