Music boxes were mechanical instruments that produced music when activated, typically by opening them. In certain instances, these boxes housed recorded audio instead of live mechanical music. The designation "music box" originated from their box-like construction and hinged lids, allowing them to be opened.
Leia Organa, the princess of Alderaan, possessed a music box. This box contained the Alderaanian lullaby Mirrorbright and was stored inside her keepsake chest. Within this music box, her adoptive father, Bail Organa, had recorded a message for Leia revealing the identities of her biological parents: Anakin Skywalker and Padmé Amidala Naberrie, as well as the existence of her twin brother, Luke Skywalker.