What is an illegal screen in basketball?

In basketball, an illegal screen occurs when a player sets a screen in an unfair or illegal manner. This can include actions such as moving into the opponent's path, making excessive or unnecessary contact, or sticking out a hip or knee to trip the defender.

Illegal screens are typically called by referees as offensive fouls, resulting in a turnover and possession being awarded to the opposing team. Players who consistently set illegal screens may also be subject to disciplinary action by the league, such as fines or suspensions.

It is important for players to understand the rules and guidelines for setting screens in basketball to avoid committing illegal screens and to help their team create scoring opportunities within the bounds of fair play.