Explain the use of screens in basketball

In basketball, when a team has the ball, one person may set a screen by blocking a defender with his body but making sure his hands are not extended. This allows the person with the ball to pass, shoot, etc. without issuing any fouls. If the person setting a screen moves while screening, the referee will call a moving screen and the ball will be inbounded by the person who moved while screening from the half court line. In any case, screens do not foul the screener for contact unless they are to do physical contact with their hands or feet.