Some writers will use "polearm" to mean "hafted weapon other than spear/pike", but properly speaking, they're all polearms. It's difficult to precisely define a spear, since there are spears with unedged conical points, single-edged heads, double-edged heads of various forms, and multi-pointed heads.

The halberd is a two-handed weapon with an axe blade topped with a spike mounted on its shaft. It can also have a hook or thorn on the backside of the axe blade for grappling mounted combatants. In contrast, the spear can be used as a two-handed or one-handed weapon.

What is the Difference Between Spear and Halberd. The main difference between a spear and a halberd lies in their design and functionality. A spear typically consists of a long pole with a pointed tip, while a halberd incorporates additional features, such as an axe blade and a hook.

Researchers suspected that a halberd or a bill sliced through the back of King Richard III's skull at the Battle of Bosworth Field on 22 August 1485, leaving his brain visible before killing him during the battle, and were later able to confirm that it was a halberd.

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.