Football is the name given to a number of ifferent team sports, all of which involve (to varying degrees) kicking a ball with the foot in an attempt to score a goal. The most popular of these sports world-wide is association football, also known as soccer and most commonly just football. The English language word "football" is also applied to gridiron football (which includes American football and Canadian football), Australian rules football, Gaelic football, rugby football (rugby league and rugby union), and related games. Each of these codes (specific sets of rules, or the games defined by them) is referred to as "football".