A polearm or pole weapon is a close combat weapon in which the main fighting part of the weapon is fitted to the end of a long shaft, typically of wood, extending the user's effective range and striking power. Polearms are predominantly melee weapons, with a subclass of spear-like designs fit for thrusting and/or throwing. Because many polearms were adapted from agricultural implements or other fairly abundant tools, and contained relatively little metal, they were cheap to make and readily available. When belligerents in warfare had a poorer class who could not pay for dedicated military weapons, they would often appropriate tools as cheap weapons. The cost of training was comparatively low, since these conscripted farmers had spent most of their lives using these "weapons" in the fields. This made polearms the favoured weapon of peasant levies and peasant rebellions the world over.
Polearms can be divided into three broad categories: those designed for extended reach and thrusting tactics used in pike square or phalanx combat; those designed to increase leverage (due to hands moving freely on a pole) to maximize angular force (swinging tactics) against cavalry; and those designed for throwing tactics used in skirmish line combat. The hook on weapons such as the halberd was used for pulling or grappling tactics, especially against horsemen. Because of their versatility, high effectiveness and low cost, there were many variants of polearm, which were much-used weapons on the battlefield. Bills, picks, dane axes, spears, glaives, guandaos, pudaos, pikes, poleaxes, halberds, harpoons, sovnyas, tridents, naginatas, bardiches, war scythes, and lances are all varieties of polearms.
Polearms were common weapons on post-classical battlefields of Asia and Europe. Their range and impact force made them effective weapons against armoured warriors on horseback, unhorsing the opponent and to some extent effective to penetrate armour. The Renaissance saw a plethora of varieties. Polearms in modern times are largely constrained to ceremonial military units such as the Papal Swiss Guard or Yeomen of the Guard, or traditional martial arts. Chinese martial arts in particular have preserved a wide variety of weapons and techniques.