Goal line (association football)

A football pitch (also known as a football field or soccer 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 surface can be either natural or artificial, but FIFA's Laws of the Game specify that all artificial surfaces must be painted green. The pitch is typically made of turf (grass) or artificial turf, although amateur and recreational teams often play on dirt fields.

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 16.5-metre (18-yard) line has occurred in the penalty area. 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.

The field descriptions that apply to adult matches are described below. Note that due to the original formulation of the Laws in England and the early supremacy of the four British football associations within IFAB, the standard dimensions of a football pitch were originally expressed in imperial units. The Laws now express dimensions with approximate metric equivalents (followed by traditional units in brackets), but use of the imperial units remains common in some countries, especially in the United Kingdom.

The pitch is rectangular in shape. The longer sides are called touchlines. The other opposing sides are called the goal lines. The two goal lines must be between 45 and 90 m (50 and 100 yd) and be the same length. The two touch lines must also be of the same length, and be between 90 and 120 m (100 and 130 yd) in length. All lines must be equally wide, not to exceed 12 centimetres (5 in). The corners of the pitch are marked by corner flags.

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