The most common formation you will likely see in British football is the 4-4-2.
It's made up of four defenders, four midfielders and two strikers.
It is an adaptable system where you have strength in midfield and plenty of width.
Having two strikers means that the front line has extra support rather than having to wait for the midfield to reach them.
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This formation, like others, tends to free up the full-backs, who will have more time on the ball than midfielders, particularly if the opposition is playing 4-4-2 as well.
In fact, some coaches see the two central midfielders in this formation as defenders and the full-backs as attackers.
This formation also offers the chance for one of the two central midfielders to get forward and support the strikers.
Sometimes the two midfielders will take turns in pushing forward to keep the defenders guessing.
It actually stems from what was a 4-2-4 system used by great Brazilian and Real Madrid sides of the past
Former England coach
But some teams, such as England, sometimes favour a more solid approach, assigning a midfielder to have a more defensive and deeper role - such as Ledley King or Jamie Carragher - to cover the defence.
This gives the more attacking midfielder greater freedom to push forward and support the strikers.
This type of formation has been called the diamond formation as the four midfielders form a diamond-like shape, and it favours a team which does not have strong wingers.