In baseball

Baseball

Baseball is a bat-and-ball sport played between two teams of nine players each. The aim is to score runs by hitting a thrown ball with a bat and touching a series of four bases arranged at the corners of a ninety-foot diamond...

, a fair ball is a batted ball that entitles the batter to attempt to reach first base. In order for a batted ball to be fair, it must be hit in such a way that it:

• settles on fair ground between home and first base, or between home and third base; or
• is on or over fair territory when bounding past first or third base; or
• touches first, second, or third base (which by rule are in fair territory); or
• touches the person of an umpire or player while the ball is on or over fair territory (unless it touches the batter in the batter's box, or bounces off the ground and immediately hits the bat); or
• passes out of the playing field in flight
  In flight
  In baseball, the rules state that a batted ball is considered in flight when it has not yet touched any object other than a fielder or his equipment....
  
   while over fair territory, or touches any part of the foul pole, including any attached screen, while in flight; or
• strikes any object for which the specific ballpark
  Baseball park
  A baseball park, also known as a baseball stadium, ball park, or ballpark is a venue where baseball is played. It consists of the playing field and the surrounding spectator seating...
  
  's ground rules specify that a batted ball striking that object is a fair ball (e.g., a roof if present)

Fair territory or fair ground is defined as the area of the playing field

Baseball field

A baseball field, also called a ball field or a baseball diamond, is the field upon which the game of baseball is played. The terms "baseball field" and "ball field" are also often used as synonyms for ballpark.-Specifications:...

 between the two foul lines, and includes the foul lines themselves and the foul poles.

On a fair ball, the batter attempts to reach first base or any subsequent base, runners

Baserunning

In baseball, baserunning is the act of running around the bases performed by members of the team at bat.In general, baserunning is a tactical part of the game with the goal of eventually reaching home to score a run. In fact, the goal of batting is generally to produce baserunners, or help move...

 attempt to advance and fielders try to record outs

Putout

In baseball statistics, a putout is given to a defensive player who records an out by one of the following methods:* Tagging a runner with the ball when he is not touching a base...

. A fair ball is considered a live ball

Live ball (baseball)

In baseball, when the ball is alive , the game can proceed. The pitcher may pitch the ball , the batter may attempt to hit such a pitch, baserunners may attempt to advance at their own risk, and the defense may attempt to put the batter or baserunners out.-Definition:The ball becomes live when the...

 until the ball becomes dead by leaving the field or any other method.

By contrast, a foul ball

Foul ball

In baseball, a foul ball is a batted ball that:* Settles on foul territory between home and first base or between home and third base, or* Bounds past first or third base on or over foul territory, or...

is a batted ball that does not entitle the batter to attempt to reach first base.