What is linesman in football?

In football, a linesman, also known as an assistant referee, is an official who assists the referee in enforcing the laws of the game. Positioned along the touchlines, the linesman primarily helps with offside calls, throw-ins, corner kicks, and goal kicks. They use flags to signal their decisions to the referee and play a crucial role in maintaining the flow and fairness of the match. Their decisions can significantly impact the outcome of the game.