Formation in football (soccer) describes how the players in a team are positioned on the pitch. Different formations can be used depending on whether a team wishes to play more attacking or defensive football.
Formations are the number of players in each area of the pitch from the defenders (not including the goalkeeper). For example 4-4-2 describes the formation as having: 4 defenders, 4 midfielders and 2 forwards. Convention is the formation can be described with 3 numbers, although 4-numbered (e.g. 4-4-1-1) and 5-numbered formations (e.g. 4-1-2-1-2) can be used. The numbering system to describe formations was not present until the 4-2-4 system was developed in the 1950s.
Formations can be altered during a game, but requires adaptations of the players to fit in to the new system. This can be due to a team wishing to defend or attack more, or due to the substitution of a player. Some formations also lend themselves to dynamically changing as players move up and down the field, e.g., the attacking 4-3-3 formation can be switched to a defensive 4-5-1 formation during a match. This system of play is currently adpated by Chelsea FC.
Formations are used in both professional and amateur football matches. However in amateur matches these tactics are sometimes adhered to less strictly. Skill and discipline on behalf of the players is also needed to effectively carry out a given formation. Formations need to be chosen with the players available in mind, and some of the formations below were created to address deficits in different types of players.