A London traffic light: how the yellow and red cards were born
English referee Ken Aston devised the cards inspired by a traffic light, after the confusion of a 1966 England-Argentina match. They debuted at the 1970 World Cup.
The yellow and red cards are universal today, but they did not always exist. Their origin lies in the mind of an English referee, Ken Aston, and in a very real problem: language.
In the England-Argentina quarter-final of the 1966 World Cup, the German referee verbally sent off Argentine captain Antonio Rattín, who did not understand the order and took several minutes to leave the pitch. There was also confusion over which players had been booked.
Aston, that tournament's head of referees, sought a solution. The inspiration came, as he told it, when he stopped at a traffic light on a London street: amber to warn, red to stop. His wife, Hilda, made the first cards out of card stock.
The invention debuted at the 1970 World Cup in Mexico. The first yellow card in World Cup history went to the Soviet Union's Kakhi Asatiani, in the opening match. The first red would take a little longer: Chile's Carlos Caszely would see it in 1974.
A gesture as simple as holding up a coloured card became a universal language that any footballer understands, whatever language they speak.
Source: Wikipedia (Ken Aston; Penalty card; Carlos Caszely).