Tactics

Four defenders, three midfielders, three forwards (a striker and two wingers). The wingers stay wide to stretch defenses and give the striker room to work. The midfield three usually has a holding player with two more attacking midfielders ahead. Barcelona made this formation their identity under Cruyff and Guardiola. Good for teams who want to dominate possession and attack.

The side of the pitch away from the ball. While the defense shifts ball side, the weak side becomes less defended. Quick switches of play exploit this - ping the ball across and suddenly the weak side attacker has space. Teams balance numbers to prevent getting caught, but there's always a trade-off between compactness ball side and coverage on the weak side.

The side of the pitch where the ball is. When defending, you want more players ball side than away from it, since that's where the danger is. "Getting ball side" means positioning yourself between your opponent and the ball. Defenders who stay ball side cut off passing lanes; those who get caught wrong side get played in behind.

Running into the space between a centre-back and full-back. That gap is the "channel." Attackers who time runs into the channel are hard to track because neither defender wants to leave their position. A good channel run, combined with a good through ball, is one of football's most effective attacking combinations. Strikers who make these runs constantly stretch defenses.

Defending a specific area rather than a specific player. Each defender covers their zone, and whoever enters that zone becomes their responsibility. It keeps the defensive shape intact but can leave attackers free between zones or let clever movement exploit the gaps. Most modern teams use zonal marking as a base, especially from set pieces.