What is the purpose of the cards in a football game?

Answer 1

They are used to give warnings to players and to indicate what kind of warning it is. A yellow card is for a serious offence. If a player gets a second yellow card, they will be sent off. A very serious offence will warrant a red card and the player is sent off immediately. By using cards it makes it easier for the crowds to know what decision the referee has made. Referees often talk to players for various reasons, so the cards help the crowds know when it is a serious issue.