Which Tolkien novel features the character Smaug?

Smaug appears in J.R.R. Tolkien’s novel The Hobbit.

Smaug is a powerful dragon who occupies the Lonely Mountain and guards the treasure once belonging to the Dwarves of Erebor. The company led by Thorin Oakenshield journeys to reclaim the mountain, with Bilbo Baggins serving as its burglar.

Bilbo discovers a weakness in Smaug’s armour during a conversation inside the dragon’s lair. He later reports that information to Bard the Bowman, who uses it to kill Smaug with the Black Arrow. The dragon’s death changes the political and military situation around the mountain.

Smaug is one of Tolkien’s best-known dragons, but he is not the first or greatest dragon in Tolkien’s mythology. That distinction is generally associated with Ancalagon the Black, who appears in the First Age stories later published in The Silmarillion.