The baseball diamond is the area of a baseball field where players play. It includes four bases (home plate, first base, second base, and third base) and an outfield fence.
There are also two on-deck circles located in foul ground between home plate and the teams’ benches. These are used by the next batter in the line-up to warm up and prepare for his at-bat.
In 1845, the first rules for the game of baseball were established by the Knickerbocker Base Ball Club of New York City. These rules specified that the distance from home to second and the distance from second to first should be 42 paces.
While this distance is still used, the basic structure and positioning of the bases has evolved little since those early days. The distance between first and second is now 90 feet, while the distance between home and third is 60 feet.
One of the most significant changes to the field occurred in 1887 when umpires were faced with an unprecedented dilemma. If a batted ball hit first or third base, the umpire had to decide which half of the base was in fair territory and which half of the base was in foul territory.
To alleviate this problem, the first and third bases were moved completely into fair territory, making it easier for umpires to judge whether a ball was hit foul or fair. However, the rules governing the positioning of second base remain a mystery. This is because second base does not entirely fall within the 90-foot square; it is actually positioned on the “corner” of the infield, which is not included in the diagram supplied with the rule.