Football refers to a family of team sports that involve kicking a ball to score goals, with different variations being popular in various regions. The term "football" can refer to association football (soccer), Australian rules football, Gaelic football, gridiron football (including American, arena, and Canadian football), International rules football, rugby league, and rugby union. These sports, often collectively known as "football codes," share common origins and have evolved from traditional ball games played around the world. The codification of these games in English public schools during the 19th century, coupled with the expansion of the British Empire, helped spread these sports globally.

The different football codes share certain fundamental elements, such as the use of a ball, goals or points scored by moving the ball to an opposing team's end of the field, and specific rules governing player conduct and equipment. The sports can be broadly divided into "carrying codes," where players primarily carry the ball, and "kicking codes," where the ball is mainly moved with the feet. Despite the differences, all codes involve common skills like passing, tackling, and evasion, with many featuring offside rules and the requirement to score by putting the ball between goalposts. The origin of the term "football" is debated, with theories suggesting it refers either to the use of feet to kick the ball or to games played on foot during medieval times.