Previously, warnings and dismissals were given verbally. This was not always easy at international matches due to language barriers.
The traffic light card idea
At the 1966 World Cup, German referee Rudolf Kreitlein tried unsuccessfully to send off Argentinean player Antonio Rattín. But Rattín either couldn’t or didn’t want to understand. He was a full head taller than referee Kreitlein (who was only 1.60m / 5ft 3in) and eventually had to be escorted off the pitch by the police.
England were Argentina’s opponents in this quarter-final and asked for clarification on the situation. Ken Aston was in charge of all the referees at this World Cup and wondered how this language barrier could be overcome.
He later said the idea came to him at a traffic light. Whether this explanation is true or just a nice story, we may never know. But it happened: The yellow card became a symbol of warning and the red card a symbol of dismissal.
At first, there were no yellow or red cards in football, and there was no suspension after a certain number of yellow cards.
What happened afterwards?
However, the cards were not used immediately and everywhere in the world. It was not until 1987, some twenty years after the first text, that the IFAB recommended at its annual meeting that „FIFA should instruct all national associations to make the use of red and yellow cards mandatory in the higher echelons of the game“.
However, it took more than 20 years for the yellow-red card to be introduced for repeated cautions and the resulting dismissal.
From the 2019/20 season, yellow and red cards will also be shown to team officials. Previously, the only options were a verbal warning or a verbal dismissal. Since this season, the hierarchy has been warning – caution (yellow card) and dismissal (red card or yellow-red card).
More recently, the blue card has been used for time penalties and the white card for fair play. However, these cards are only used on an experimental basis at regional level.