A similar tactic is called a "delaying action". The object is for a smaller force to harass a larger force and delay their advance. This while inflicting as much damage as they can to the larger force without directly engaging them. The purpose of a delaying action is to allow an army's main force to disengage an enemy while maintaining good order. The main force is given the time necessary to set up a new defensive position. The small force protecting the larger force is called a rearguard. A famous rearguard example was given in the "Song of Roland". Roland, nephew of Charlemagne commanded the rearguard at the Battle of Roncevaux Pass. He and his men protected the rear of the Frankish army while they retreated back to France. In this delaying action, Roland and his men were all killed in an ambush.