Throwing is an action which consists in accelerating a projectile and then releasing it so that it follows a ballistic trajectory, usually with the aim of impacting a remote target. This action is best characterized for animals with prehensile limbs: in this case the projectile is grasped, while the limb segments impart a motion of the hand through compounded mechanical advantage. For other animals, the definition of throwing is somewhat unclear, as other actions such as spitting or spraying may or may not be included.
Primates are the most capable throwers in the animal kingdom, and they typically throw feces as a form of agonistic behavior. Of all primates, humans are by far the most capable throwers. They throw a large variety of projectiles, with a much greater efficacy and accuracy. Humans have thrown projectiles for hunting and in warfare – first through rock-throwing, then refined weapon-throwing (e.g. spear), and into modern day with hand grenades and tear gas canisters.
If humans initially threw objects by hand, they very early designed tools to improve the efficiency of their throwing techniques. The sling, the bow and arrow, and various models of catapults are notable examples of throwing mechanisms.
With the advent of gun powder, research in throwing mechanisms as ranged weapons essentially halted, but throwing either by hand or with mechanical assistance has persisted for recreational purpose or as a form of exercise. Throwing is thus still performed in many sports and games, particularly ball games, and in throwing sports the action is the main determiner of the outcome.