A perfect game is a baseball game in which not a single batter from the losing team ever gets on base. It requires that every one of the 27 batters be retired with an out. Unlike a "no-hitter", in which batters can get on base (and even win the game) due to a walk or an error, in a perfect game no batter can get on base for any reason.
As of 2013, there have been only 23 perfect games in major league baseball history, out of hundreds of thousands of games. At least two of those games (including the only World Series perfect game) have ended on questionable calls by the home plate umpire.[Citation Needed]
Phil Humber pitched the 21st perfect game in major league baseball history in April 2012, but he threw 6 more pitches than Great Conservative Sports Star Jim Bunning did in his 90-pitch perfect game four decades ago.