Bilbo Baggins named the sword he took from the trolls Sting in J.R.R. Tolkien’s The Hobbit.
Bilbo found the blade in the trolls’ hoard after Gandalf and the Dwarves discovered the trolls had been turned to stone by sunrise. Although it was a small sword by the standards of Elves and Men, it was an effective weapon for Bilbo and later became especially useful against giant spiders.
Sting was made by Elves in the First Age, long before Bilbo’s adventure. Its blade glowed blue when Orcs or Goblins were nearby, a warning that repeatedly helped Bilbo and later Frodo. The weapon therefore connects the apparently modest adventure in The Hobbit with the much older history of Middle-earth.
Glamdring and Orcrist were the larger Elven blades found in the same troll hoard. Gandalf took Glamdring, while Thorin Oakenshield claimed Orcrist. Andúril was a different sword, reforged for Aragorn from the shards of Narsil.