This document discusses the rules around legal guarding position and blocking/charging calls in basketball. It defines legal guarding position as having both feet on the court and facing the offensive player. It states that a defender in legal position can move in any direction except toward the offensive player. Blocking is illegal contact that impedes an opponent, while charging is called when an offensive player pushes into a defender's torso. The offensive player must stop or change direction to avoid contact with a defender in legal position or get their head and shoulders past them prior to contact.