Origin Of Yellow And Red Cards In Soccer (Football)

Yellow Card – Indicates a formal “caution” for any of the following 7 offenses:
“unsporting behavior” – this includes hard fouls; holding an opponent or deliberately handling the ball for the purpose of preventing an opponent from gaining possession of the ball; faking an injury; saying things that are designed to confuse or distract an opponent; harassment (such as jumping around, shouting or making gestures to intentionally distract an opponent; jumping in front of a corner kick, free kick or throw-in; worrying the goalkeeper or trying to prevent him from putting the ball into play; & adopting a threatening posture), gaining an unfair advantage by leaning on, climbing on the back of, or holding a teammate or the goal; blatant cases of holding and pulling an opposing player or his uniform; any action designed to deceive the Referee; and behavior which in the Referee’s judgment is unsporting or causes an unfair advantage,
dissent by word or actions,
persistently breaking the rules,
delaying the restart of play,
defenders failing to stay the proper distance away from the kicker on a corner kick or free kick (see” Corner Kick” & “Free Kick”),
entering the field without the referee’s permission
deliberately leaving the field without the referees permission.
A player who receives 2 Yellow Cards is given a Red Card & ejected. FIFA rules do not require a player to leave the field for the first yellow card. However, some leagues’ rules do. You must go by your league’s rules. (See “Yellow Card” & “Worrying The Goalkeeper”).

Red Card – A player must be shown a Red Card and “sent off” (i.e., made to leave the field) for the 7 offenses listed below. A player shown a “Red Card” & sent off may not be replaced during that game (i.e., his team must play a player “short” for the rest of the game; however, in some leagues a player may be replaced if he is ejected for receiving a second Yellow Card). The 7 offenses for which a player must be shown a Red Card and sent off are:
serious foul play (includes any use of excessive force or brutality against an opponent when challenging for the ball. Examples include a dangerous slide tackle from behind, or an “over the top tackle” in which a player raises his foot so the cleats could hit a player, or a two footed tackle that takes down the opponent. FIFA has broadened this definition by saying that “Any player who lunges at an opponent in challenging for the ball from the front, from the side or from behind using one or both legs, with excessive force and endangering the safety of an opponent is guilty of serious foul play. For current rules visit http://www.fifa.com, Laws of the Game. The above quote is from Questions and Answers, Additional Instructions for Referees).
violent conduct,
spitting at anyone,
a deliberate hand ball to deny an obvious goal scoring opportunity,
fouling an opponent to prevent an obvious goal scoring opportunity (e.g., holding to stop a breakaway),
using offensive or threatening language,
or receiving a second yellow card in one game.

Source(s):

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