How big is a baseball field, and what are the bat and ball rules?

• The infield: "a 90-foot square (27.43 m2)", measured to the back of each base and the back point of home plate.
• The outfield: 275 feet or more to the fence down the foul lines, and 400 feet to centre field.
• Home plate: a five-sided slab 17 inches wide, facing the pitcher.
• The bases: bags 15 inches square.
• The rubber: 24 by 6 inches, at 60 feet 6 inches.
• The mound: the rubber is 10 inches above home plate.
• The ball: yarn wound round a small core, covered in white leather, 9 to 9.25 inches round.
• The bat: a smooth round stick, not more than 42 inches long or 2 5/8 inches across.
• Wood only: players may use only one-piece wooden bats on the WBSC approved list. Composite bats are prohibited.
• Gloves: no more than 13 inches long, except the catcher's mitt, which may be any size.
• Helmets: batters and runners must wear them, with double ear flaps at under 18 and below.
• The catcher: helmet and face mask are compulsory.

The glossary has the diamond, the base, the home plate, the pitcher's mound, the catcher and the outfielders.

The 90 feet between bases is finely balanced: a ground ball fielded cleanly and a fast runner arrive at first base at almost the same time, and that keeps the game close on every play. Wooden bats are kept at the top level because the ball comes off them more slowly than off metal, which protects fielders and pitchers.