The dragon killed by Bard in J.R.R. Tolkien’s The Hobbit is Smaug.
Smaug occupies the Lonely Mountain and guards the treasure that once belonged to the Dwarves of Erebor. After Bilbo Baggins discovers a weak, unarmoured place in the dragon’s body, he tells the information to the thrush outside the mountain. The bird conveys it to Bard, a descendant of the former kings of Dale.
Bard uses the Black Arrow to shoot Smaug in the exposed spot beneath his left breast. Smaug’s death causes him to fall onto Lake-town, also called Esgaroth, destroying much of the settlement. Bard then becomes an important leader in the rebuilding of Dale.
Smaug is distinct from other dragons in Tolkien’s mythology. Glaurung and Ancalagon belong to the older First Age stories, while Scatha is another dragon associated with the northern lands. Smaug is the central dragon of The Hobbit and one of Tolkien’s most memorable speaking villains.