Ballparks

A baseball park, also known as a ballpark or diamond, is a venue where baseball is played. A baseball park consists of the playing field and the surrounding spectator seating. While the diamond and the areas denoted by white painted lines adhere to strict rules, guidelines for the rest of the field are flexible.

The term "ballpark" sometimes refers either to the entire structure, or sometimes to just the playing field. A home run where the player makes it around the bases, and back to home plate, without the ball leaving the playing field is typically called an "inside-the-park" home run. Sometimes a home run over the fence is called "out of the ballpark", but that phrase more often means a home run that clears the stands and lands outside the building. The playing field is most often called the "ballfield", though the term is often used interchangeably with "ballpark" when referring to a small local or youth league facility.

A baseball field can be referred to as a diamond. The infield is a rigidly structured diamond of dirt containing the three bases, home plate, and the pitchers mound. The space between the bases and home is normally a grass surface, save for the dirt mound in the center. Some ballparks, like Toronto's Rogers Centre, have grass or artificial turf between the bases, and dirt only around the bases and pitcher's mound. Others, such as Koshien Stadium in Hyōgo Prefecture, Japan, have an entirely dirt infield.

Two white lines run out from the home plate area, aligned with first and third bases. These are the foul lines or base lines, usually differentiated by referring to them as the first base line, or the third base line. If a ball hit by the batter lands outside of the space between these two lines, or rolls out of this space before reaching first or third base, the ball is "foul" (meaning it is dead and the play is over). If it lands between or on the lines, it is "fair". At the end of the lines are two foul poles, which help the umpires judge whether a ball is fair or foul. These "foul poles" are actually in fair territory, so a ball that hits them on the fly is a home run (if hit on the bounce, it is instead an automatic double).

On either side of home plate are the two batter's boxes (left-handed and right-handed.) This is where the batter stands when at bat. Behind home is the catcher's box, where the catcher and the home plate umpire stand.

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