How Baseball Works

By: Kevin Bonsor & Joe Martin

Baseball Diamond

Layout of a typical baseball diamond

Like any sport, the field on which the game is played defines baseball. Once you understand the field, you can then better understand how the game works. The baseball field is unique in sports. Unlike most team sports that play on a rectangular field (e.g. basketball, football and soccer), baseball is played on a wedge-shaped field, which resembles a quarter of a circle. The field is often referred to as a diamond.

The baseball diamond is defined by two lines, called foul lines, which meet at home plate and extend outward, perpendicular to each other. These foul lines create a boundary on each side of the field between fair territory and foul territory. Everything on the outside of the foul line, including the area behind home plate, is considered foul territory. Foul territory is designated as "out of play," which means baseballs hit there don't count as a hit. However, the ball can be caught in foul territory. Foul territory also includes:


  • Team dugouts - The sheltered area on either side of the field where players stay when they aren't on the field
  • Bullpen - The area where pitchers practice before entering the game
  • Base coach's boxes - An area next to first and third base that coaches stand in to instruct the base runners
  • On-deck circles - A small circle outside the dugout where the player next in order to bat stands to practice his swing before batting
  • Seats - The seats of a typical stadium wrap around the entire field. Almost the only seats that aren't in foul territory are those beyond the outfield wall between the foul lines.

Inside the foul lines, or fair territory, is where most of a baseball game's action takes place. Fair territory is subdivided into the infield and the outfield. On most fields, the dividing line between the two is where the grass of the outfield meets the dirt of the infield. The parts of the infield include:

  • Bases - The Bases are the four stations (first base, second base, third base, and home plate) that players must run to after hitting the ball into play. Each base is 90 feet (27 m) apart in a Major League Baseball game. A run is scored when a player reaches home plate.
  • Base paths - The base path is the line between each base that the player must run along to reach a base. A player can be called out for running outside of the path.
  • Pitcher's mound - The pitcher's mound is the raised mound of dirt in the middle of the infield on which the pitcher stands.
  • Batter's box - The batter's box is marked off by two small rectangles flanking home plate. The batter must stand within the borders of the box to hit.

Now that you are familiar with the geography of a baseball field, let's look at the players and their positions.