In a soccer match, the referee is basically the most important and respected among other officials on the pitch. It is the referee who carries a whistle and uses it in signaling the start and stop of play which includes the following:
Penalties and Free Kicks
In case of a foul, the referee will be blowing his whistle in order to award the opposing either a free kick or a penalty kick. The latter is usually given if the foul took place within the penalty area and penalized the player who has committed it.
More often than not, the first resource of a referee is stern verbal warning.
Yellow and Red
Beyond that, the referee may also show players yellow card and take their name. In soccer, this is also called as “booking”. This is due to the reason that referees are writing down the name of player in their little book. Players who get 2 yellow cards in a single game are automatically sent off and their team has to continue with one player less on the field.
Additionally, the referee is carrying a red card which is used as punishment for more serious infractions committed by players.