The World Series—or Fall Classic—annually pits the pennant winners of the American and National leagues in a best-of-seven series for the Major League Baseball championship. 

The New York Yankees have won 27 World Series titles, by far the most by any team. The St. Louis Cardinals are second with 11, followed by the Boston Red Sox and Philadelphia/Oakland A's, who are tied with nine apiece.

1903: First World Series Played

The first modern World Series was a best-of-nine series played in 1903 between the American League champion Boston Americans (later Red Sox) and National League champion Pittsburgh Pirates. The Americans won the final four games to win the championship, 5-3. Boston pitcher Cy Young, MLB’s all-time leader in wins (511), won Games 5 and 7. (The only other best-of-nine World Series occurred in 1919, 1920 and 1921.)

The World Series, which typically begins in October, has featured some of the most dramatic moments in sports history. Among them were an over-the-shoulder catch by the New York Giants’ Willie Mays (Game 1, 1954, vs. Cleveland Indians) and Series-winning home runs by the Pittsburgh Pirates’ Bill Mazeroski (Game 7, 1960, vs. the New York Yankees) and the Toronto Blue Jays’ Joe Carter (Game 6, 1993, vs. the Philadelphia Phillies). A dramatic, game-winning home run in the ninth inning by Los Angeles' Kirk Gibson in Game 1 in 1988 set the tone for that World Series, won by the Dodgers over the Oakland A's in five games.

Blunders and controversy have rocked some World Series. The most infamous World Series scandal involved the 1919 Chicago White Sox. 

1919 'Black Sox' World Series Scandal

The scandal involved eight members of the Chicago White Sox, who were accused after the World Series of throwing games against the Cincinnati Reds for money from a gambling syndicate. Cincinnati won the eight-game series, 5-3. 

The players involved—dubbed "Black Sox"—were acquitted in court but banned from the sport by Major League Baseball commissioner Kenesaw Mountain Landis. “Shoeless” Joe Jackson, one of the greatest hitters in MLB history, was the most famous of the banned players. His .356 career batting average ranks as one of the best in MLB history. Despite his excellent credentials for the Baseball Hall of Fame, Jackson remains on MLB's ineligible list for the honor—a decision that remains controversial. 

READ MORE: Did Shoeless Joe Jackson Conspire to Throw the 1919 World Series?

New York Yankees Dominate World Series

In 1923, the Yankees—led by outfielder Babe Ruth, who hit 41 home runs during the regular season—won their first World Series championship. New York followed its initial championship with World Series titles in 1927 and 1928. The 1927 team, considered one of the greatest teams in MLB history, won 110 games during the regular season and swept the Pittsburgh Pirates in four games in the World Series.

READ MORE: 10 Things You May Not Know About Babe Ruth

In addition to Ruth, who hit a then-MLB-record 60 home runs during the regular season, the team featured first baseman Lou Gehrig (47 home runs and 173 runs batted in), and pitcher Waite Hoyt, who won 22 games. Six Yankees players from that team were enshrined in the Baseball Hall of Fame in Cooperstown, New York: Ruth, Gehrig, Hoyt, pitcher Herb Pennock, second baseman Tony Lazerri and outfielder Earle Combs.

The Yankees continued their dominance of the sport into the 1930s (five championships), 1940s (four titles) and 1950s (six titles). In defeating the Brooklyn Dodgers in the “Subway Series” in seven games in 1956, Yankees pitcher Don Larsen pitched a perfect game in Game 5 on October 8, 1956. It remains the only time in World Series history a pitcher has retired all opposing 27 batters for a perfect game.

In addition to winning the most World Series championships, the Yankees have appeared in more World Series (40) than any other team. Only the Dodgers, with 14, have lost more World Series than the Yankees (13.)

New York’s loss in the 1960 World Series was particularly heartbreaking for the Yankees and their fans. Despite outscoring the Pirates, 55-27, New York lost the World Series in seven games. In Game 7 at Forbes Field in Pittsburgh, second baseman Bill Mazeroski's home run in the bottom of the ninth inning over the left-field wall won the title for the Pirates. It was one of the most dramatic moments in World Series history.

READ MORE: The Most Dramatic Home Run in World Series History

Other Notable World Series

In 1975, the Cincinnati Reds, known as the "Big Red Machine" for their 1970s dominance, defeated the Boston Red Sox in seven games. The Reds won 108 games during the regular season and swept the Pittsburgh Pirates in the playoffs in three games. In Game 6 at Fenway Park in Boston, Red Sox catcher Carlton Fisk hit one of the most dramatic home runs in World Series history. The ball struck the foul pole of the "Green Monster," Fenway Park's iconic left-field wall, as Fisk waved his arms to will the ball to stay fair.  

READ MORE: What Was the Curse of the Bambino—and How Was Baseball's Greatest Hex Broken?

In 1986, the New York Mets defeated the Boston Red Sox in seven games. In the top of the 10th inning of Game 6, the Red Sox took a two-run lead. But the Mets rallied for three runs to win, 6-5. The winning run scored when a ground ball rolled between the legs of Red Sox first baseman Bill Buckner for an error—one of the worst gaffes in World Series history. The Mets won Game 7, 8-5. The loss kept alive an ignominious streak for the Red Sox, who had not won a World Series since 1918.

In 1991,  the Minnesota Twins defeated the Atlanta Braves in seven games. Five of the games were decided by one run. Both teams finished in last place the previous season. In Game 7, Jack Morris of the Twins pitched all 10 innings of Minnesota's 1-0 win.

In 2004, the Boston Red Sox swept the St. Louis Cardinals in four games to win their first World Series since 1918 and end "The Curse of the Bambino." The Cardinals did not have the lead in any game.

READ MORE: 6 of the Wildest Moments from the 1986 New York Mets Championship Season

1989: Earthquake World Series

On October 17, 1989, a magnitude 6.9 earthquake rocked northern California during Game 3 of the World Series between the San Francisco Giants and Oakland Athletics at Candlestick Park, forcing postponement of the matchup. The World Series resumed 10 days after the earthquake, which killed 67, injured more than 3,700 and caused an estimated $5 billion in property damage.

Less than a half-hour before the game was to start, the quake hit, shaking Candlestick Park. When the shaking stopped, there was a brief lightheartedness at the ballpark—the Giants even blared Queen's "We Will Rock You" over the public-address system. Then reality set in.

The A's swept the World Series in four games. 

1994: Cancellation of World Series 

The World Series was not played only twice—in 1904, one year after the first World Series, when the New York Giants refused to play the American League champion Boston Americans, and in 1994, when the season was cancelled because of a players strike. The Montreal Expos (74-40) and New York Yankees (70-43) appeared to be on a collision course for the World Series that season.

World Series Most Valuable Player Award

Since 1955, the World Series Most Valuable Player Award has been given to the player whose performance was most impactful. The award, now voted on by media, officials and online by fans, has gone to the player from the winning team at every World Series except one. In 1960, New York Yankees second baseman Bobby Richardson won the award following the team's loss in a seven-game series to the Pittsburgh Pirates. In 2017, the award was named in honor of Baseball Hall of Famer Willie Mays.

Sources:

World Series, Baseballreference.com

Major League Baseball

National Baseball Hall of Fame