Spears are weapons consisting of long poles, usually made of wood with a sharpened end made of metal or stone attached to the end of the shaft.
Spears are used for both hunting and warfare.
The Elves probably made their own and used it for hunting while still in eastern middle-earth before the Great Journey. After returning to Middle-earth in pursuit of Morgoth, the use of the spear changed from just hunting to use in war.
When men awoke in the First Age, they probably made their own and used it for hunting or perhaps warfare. Later, learning from the elves, they probably perfected it and passed it down to future generations up to Númenor and onward.
- Spear at the Wikipedia