Smaug is the dragon who attacks Lake-town in J.R.R. Tolkien’s The Hobbit.
Smaug takes Erebor, the Lonely Mountain, from the Dwarves and drives them into exile. He then sleeps on the immense treasure hoard beneath the mountain for many years. Bilbo Baggins enters the lair during the Dwarves’ quest and discovers that a bare patch in Smaug’s jewelled hide leaves him vulnerable.
After learning of this weakness from Bilbo, the people of Lake-town are warned of the dragon’s danger. Bard the Bowman uses the information to kill Smaug with a black arrow. Tolkien’s other dragons belong to different ages and stories: Glaurung appears in The Silmarillion tradition, Ancalagon in the First Age, and Scatha in a later history of the Rohirrim. Smaug is therefore specifically the dragon of The Hobbit and Erebor.