text: Unqualified , the word football applies to whichever form of football is the most popular in the regional context in which the word appears , including American football , Australian rules football , Canadian football , Gaelic football , rugby league , rugby union and other related games .
simplified: Football can also mean American football ( gridiron ) , è é `` ( Ancient Chinese football ) , rugby union , rugby league , Australian Rules Football , Gaelic football or Canadian football .