In The Legend of Zelda: Majora's Mask, what is the name of the salesman who sells masks?

In The Legend of Zelda: Majora's Mask, the salesman who sells masks is the Happy Mask Salesman.

He is a mysterious traveling merchant who first appeared in Ocarina of Time, where Link can borrow and sell masks for him. In Majora's Mask, he has a much larger role: he arrives in Clock Town carrying a huge pack of masks and asks Link to recover Majora's Mask after it is stolen by the Skull Kid.

The Happy Mask Salesman is closely tied to the game's unsettling atmosphere. He often appears cheerful and polite, but his sudden anger when Link fails to return the mask reveals a far more intense personality. He also teaches Link the Song of Healing, which restores Link's human form after the Skull Kid's curse.

A common mix-up is calling him simply the “Mask Salesman.” That description is understandable, but Happy Mask Salesman is the character's canonical name. Tingle and the Scarecrow are separate characters, and neither sells masks.