Overview
Curl or bend in association football is spin on the ball which makes the ball move in a curved direction. When kicking the ball, the inside of the foot is often used to curl the ball, but this can also be done by using the outside of the foot. Similar to curl, the ball can also swerve in the air, without the spin on the ball which makes the ball curl.
Curling or bending the ball is especially used in free kicks, shots from outside the penalty area and crosses. Differences between balls can affect the amount of swerve and curl: traditional leather footballs were too heavy to curl without great effort, whereas lighter modern footballs curl more easily.
Nomenclature
The deviation of a ball from the straight path in the air is known as the curl, or swerve; however, the spin on the ball that causes this is also known as the curl. Shots that curl, bend, or swerve are known as curlers, or in extreme cases, banana shots. The technique of putting curl on a ball with the outside of the foot is sometimes known as a trivela, a Portuguese term, with Ricardo Quaresma a notable user of this skill. The topspin technique of putting straight curl (instead of side curl) on a ball is known as a dip or dipping shot. The 1950s Brazilian star Didi is thought to have invented this technique, and used it frequently when taking free kicks, which were known as folha seca ("dry" or "dead leaf," in Portuguese) free kicks. Today it is commonly known as the knuckleball technique; this technique has also been described in the media as the "tomahawk", or even the "maledetta" ("accursed," in Italian).
Usage
From Wikipedia (CC BY-SA 4.0).