Football is all about scoring and stopping goals.
But there are many different tactics that can be used in pursuit of these aims - and that's where the manager earns his crust.
It might be better to play more defensively to hold on to a lead. Or, if the team is losing, a more attacking set-up that allows the players to push further forward may be required.
To alter the way the team is playing requires a change to the structure.
Traditionally, teams play in a 4-4-2 formation - that is four defenders, four midfielders and two strikers. But, as the game has progressed and developed, managers and players have experimented with many variations of team formations.
Adaptability is the key and the best managers can change formations as the game progresses
The type of formation selected by the manager reflects the sort of football you can expect them to play, so understanding what the most commonly used formations signify is key to understanding football.
The most common and adaptable formation in modern football, the weakness of 4-4-2 is the gaps between the central defenders, midfielders and the strikers. As such, a huge burden is placed on the central midfield to augment defense and attack.
However, the two sides’ contrasting attitudes in central midfield reflects the subtle variations in the 4-4-2. Whereas Manchester United’s first-choice midfield of Paul Scholes and Roy Keane married a powerful but diminutive mixture of a goal-scoring attacking midfielder and a box-to-box tough-tackler, Arsenal emphasised a tall, powerful combination with their own tough-tackling box-to-box midfielder, Patrick Vieira, and a strict holding midfielder in Gilberto Silva.
A formation which has grown in popularity in recent times, the 4-5-1 is fundamentally defensive, but can be tweaked to provide more of an offensive threat. The essential qualities of the 4-5-1 are a three-man central midfield and a lone striker, typically a target man. By packing the midfield, a technically strong passing side will come unstuck and provide opportunities for counter-attacking football. When on the attack, the 4-5-1 is heavily dependent on the wingers supporting the lone striker.
In some ways, the 4-3-3 is covered in the description of the 4-5-1. However, whereas the 4-5-1 starts with the wingers supporting the central midfielders, the 4-3-3 encourages the wingers to act as true forwards and the formation generally emphasises attack more than defense.
The diamond in the formation refers to the midfield, with an attacking midfielder and a holding midfielder employed and flanked by two wingers, who move in-field slightly to shore up the gaps in the centre. To cover for the lack of width in the side, the full-backs become wingbacks and start slightly higher up the pitch.
In theory, the 5-3-2 is a purely defensive-minded line-up. The three central defenders provide extra resoluteness, while the three in midfield are all located around the centre circle. There is also a notable gap between midfield and attack, and the wing-play is the sole responsibility of the fullbacks.