Baseball is a bat-and-ball sport played between two teams of nine players each. The goal of baseball is to score runs by striking a thrown ball with a bat and touching a series of four markers called bases arranged at the corners of a ninety-foot square, or diamond. Players on one team (the batting team) take turns hitting while the other team (the fielding team) try to stop them from scoring runs by receiving hitters out in any number of ways. A player on the batting team can discontinue at any of the bases and hope to score on a teammate's hit. The teams switch between batting and fielding whenever the fielding team gets three outs. One turn at bat for each team constitutes an inning; nine innings make up a professional game. The team by way of getting more runs at the end of the game wins.