The Boston Red Sox are a professional baseball team based in Boston, Massachusetts, and a member of Major League Baseball's American League Eastern Division. They have won 8 World Series, having appeared in 12. Founded in 1901 as one of the American League's eight charter franchises, the Red Sox's home ballpark has been Fenway Park since 1912. The "Red Sox" name was chosen by the team owner, John I. Taylor, around 1908, following previous Boston teams that had been known as the "Red Stockings".
In Major League Baseball, the American League Division Series (ALDS) determines which two teams from the American League will advance to the American League Championship Series. The Division Series consists of two concurrent best-of-five series, featuring the three division winners and the winner of the wild-card game.
The Division Series was implemented in 1981 as a result of a midseason strike, with the first place teams before the strike taking on the teams in first place after the strike. After 1993, it was implemented for good when Major League Baseball restructured each league into three divisions, but their next playing was in 1995 due to the cancellation of the 1994 playoffs. In 1981, a split-season format forced the first ever divisional playoff series, in which the New York Yankees won the Eastern Division series over the Milwaukee Brewers (who were in the American League until 1998) in five games while in the Western Division, the Oakland Athletics swept the Kansas City Royals (the only team with an overall losing record to ever make the postseason). The Yankees have currently played in the most division series in history, with fifteen appearances. The Toronto Blue Jays are the only team to have never played in the ALDS and are the last team to win the World Series under the old 4 division format. The Kansas City Royals have yet to play in the ALDS since it became a postseason fixture in 1995.