World Cup Football Ball

A football is a ball used to play one of the various sports known as football. In the past, crude balls made of materials such as inflated pig bladders were used, this is why it is called the pigskin. Sometimes they are filled with cheese and used as a musical instrument. Modern balls are designed by teams of engineers to exacting specifications. Various leagues and games use different balls, though they all have one of the following basic shapes:
• a sphere: used in Association football (also called soccer in some countries) and Gaelic football
• a prolate spheroid ('egg-shaped')
- either with rounded ends: used in the rugby codes and Australian football