The baseball infield is the area of the field located within the diamond formed by the four bases: first base, second base, third base, and home plate. It is typically made of grass and dirt, with the dirt portion known as the infield dirt. The infield is crucial for gameplay, as it is where most defensive plays occur and where runners advance between bases. In the infield, there are four primary positions: pitcher, catcher, first baseman, and shortstop. The second baseman and third baseman also play key roles in fielding ground balls and making throws to get runners out. The infield's layout and surface can significantly affect the speed and direction of the ball during play.