On a baseball field, there are four bases. The bases form a diamond that goes around the field to the right from the starting base. The starting base is called "home plate". Home plate is a pentagon, which is a shape that has five sides. First base is on the right side of the field, second base is at the top of the infield, third base is on the left side of the field, and home plate is at the back of the field, where the catcher plays.