The World Series is Major League Baseball's (MLB) annual championship, first contested in 1903 between the champion teams of the American League (AL) and National League (NL). This best-of-seven playoff, traditionally held in October and famously known as the "Fall Classic," awards the winning team the Commissioner's Trophy. Over the years, the qualification process evolved significantly, moving from simply the league's best regular-season team before 1969 to a multi-round postseason structure including League Championship, Division, and Wild Card series today. Home-field advantage rules have also changed, most recently in 2017 to favor the league champion team with the better regular-season record. Through the 2024 season, the AL has claimed the title 68 times to the NL's 52 across 120 contests. While precursor "World's Series" competitions between the National League and American Association existed from 1884 to 1890, MLB does not officially recognize these 19th-century matchups as part of modern World Series history.