A football pitch (also known as a football field) is the playing surface for the game of association football. Its dimensions and markings are defined by Law 1 of the Laws of the Game, "The Field of Play". The pitch is typically made of natural turf or artificial turf, although amateur and recreational teams often play on dirt fields. Artificial surfaces must be green in colour.
All line markings on the pitch form part of the area which they define. For example, a ball on or above the touchline is still on the field of play, and a foul committed over the line bounding the penalty area results in a penalty. Therefore, a ball must completely cross the touchline to be out of play, and a ball must wholly cross the goal line (between the goal posts) before a goal is scored; if any part of the ball is still on or above the line, the ball is still in play. 1