Offside is an offence in football and the opposing team receives an indirect free kick. A player is off side when he is nearer to his opponentÃs goal line than both the ball and the second last opponent.
A player in offside position is only penalised if, at the moment the ball touches or is played by a player of his own team he is in the opinion of the referee involved in active play, interfering with play, interfering with an opponent or gaining an advantage by being in that position.
There is no offside offence if the player receives the ball directly from a goal kick, a throw in or a corner.