In baseball, this is a batted ball that leaves the field of play, not allowing the player to attempt to make it on base. The fielders can make an attempt at a putout on the foul ball, which is known as a "foul out". In the event of a foul ball that is not caught, the player receives a ball on his or her hit count and is required to take another pitch.
There are several scenarios in which a ball is determined to be a foul ball. If the batted ball lands into the infield but rolls or bounces into foul territory before passing first or third base and hasn't touched a player or umpire, then the ball will be deemed a foul ball. If the ball settles in foul territory it will be deemed a foul ball, unless it hit the ground within the outfield before reaching foul territory.