FIFA Laws of the Game

The Laws of the Game (LOTG) are the codified rules that help define association football. They are the only rules of association football subscribed to by the sport's governing body FIFA. The laws mention the number of players a team should have, the game length, the size of the field and ball, the type and nature of fouls that referees may penalise, the frequently misinterpreted offside law, and many other laws that define the sport. During a match, it is the task of the referee to interpret and enforce the Laws of the Game.

There were various attempts to codify the rules of football in England in the mid-19th century. The extant Laws date back to 1863 where a ruleset was formally adopted by the newly formed Football Association. The original Laws were heavily influenced by the Cambridge rules and their early development saw substantial influence from the Sheffield Rules. Over time the Laws have been amended, and since 1886 they have been maintained by the International Football Association Board.

The current Laws of the Game (LOTG) consist of seventeen individual laws, each law containing several rules and directions:

In 1997, a major revision dropped whole paragraphs and clarified many sections to simplify and strengthen the principles. These laws are written in English Common Law style and are meant to be guidelines and goals of principle that are then clarified through practice, tradition, and enforcement by the referees.

The actual law book had long contained 50 pages more of material, organized in numerous sections, that included many diagrams but were not officially part of the main 17 laws. In 2007, many of these additional sections along with much of the material from the FIFA Questions and Answers (Q&A), were restructured and put into a new "Additional Instructions and Guidelines for the Referee" section. In the 2016/2017 revision of the Laws, the material from this section was folded into the Laws themselves.

Referees are expected to use their judgement and common sense in applying the laws; this is colloquially known as "Law 18".

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