A sling is a projectile weapon typically used to throw a blunt projectile such as a stone, clay, or lead "". It is also known as the shepherd's sling. A sling has a small cradle or pouch in the middle of two lengths of cord. The sling stone is placed in the pouch. The middle finger or thumb is placed through a loop on the end of one cord, and a tab at the end of the other cord is placed between the thumb and forefinger. The sling is swung in an arc, and the tab released at a precise moment. This frees the projectile to fly to the target. The sling essentially works by extending the length of a human arm, thus allowing stones to be thrown much farther than they could be by hand. The sling is inexpensive and easy to build. It has historically been used for hunting game and in combat. Film exists of Spanish Civil War combatants using slings to throw grenades over buildings into enemy positions on the opposite street. Today the sling is of interest as a wilderness survival tool and an improvised weapon.