What is a Ball?

A ball is any round, protuberant object that is either hollow or solid. Balls play a large role in many sports and games. In baseball, for example, a baseball pitch does not pass over the home plate, but rather over the batter’s shoulders and knees. Balls are also used in the military to propel a projectile and provide low friction bearings. They are also used in black-powder weapons to hurl stone or metal balls.