The World Series is the annual championship series of North American-based Major League Baseball (MLB), played since 1903 between the American League (AL) and National League (NL) champions. The winner of the World Series championship is determined through a best-of-seven playoff and awarded the Commissioner's Trophy. As the series is played in October, which falls during autumn in North America, MLB also refers to it as the Fall Classic. The most recent World Series was won by the San Francisco Giants, who defeated the Detroit Tigers in a four-game sweep in 2012. The New York Yankees of the AL have played in 40 World Series and won 27, the Oakland/Philadelphia Athletics have played in 14 and won 9, and the Boston Red Sox have played in 12 and won 7, including the first World Series. In the NL, the San Francisco/New York Giants have appeared in 19 World Series and won 7, the St. Louis Cardinals have played in 18 and won 11, and the Los Angeles/Brooklyn Dodgers have appeared in 18 and won 6.