The boards surrounding the ice help keep the puck in play and they can also be used as tools to play the puck. Players are permitted to bodycheck opponents into the boards as a means of stopping progress. The referees, linesmen and the outsides of the goal are "in play" and do not cause a stoppage of the game when the puck or players are influenced (by either bouncing or colliding) into them. Play can be stopped if the goal is knocked out of position. Play often proceeds for minutes without interruption. When play is stopped, it is restarted with a faceoff. Two players face each other and an official drops the puck to the ice, where the two players attempt to gain control of the puck. Markings (circles) on the ice indicate the locations for the faceoff and guide the positioning of players.