Sting, any fan of The Lord of the Rings knows the name of Bilbo Baggins long knife. A weapon that maintained a keen edge, glowed with a pale blue light when orcs were near, and could harm the likes of Shelob herself. Possibly the first magic item to be found in a creatures treasure pile and a common inspiration in the game D&D.
Weapons carrying enchantments are common in D&D, ranging from the lowly +1 sword to artifacts such as Axe of the Dwarvish Lords. Magic weapons have two uses in D&D; the first is to give the character who wields it the bonuses inherent in the weapons design and the second to be used to harm those creatures who are immune to normal weapons. Unlike Sting, most weapons in D&D are not used for the life of the character, but are either discarded or enchanted with greater powers as the character rises in power. So a 4th level character may be happy with a +1 sword, where a 15th level character may wield a +4 elemental sword of fire.