Football, commonly known as soccer, is played between two teams of 11 players using a spherical ball on a rectangular field. The history of football can be traced back to medieval England, though the sport is now played professionally worldwide under a standardized set of rules. The objective is to score more goals than the opposing team by kicking the ball into their goal. Major international competitions include the World Cup held every four years featuring national teams from around the world, and continental championships organized within each confederation.