Uta is a world-famous singer or "diva" and the adopted daughter of the Emperor Red-Haired Shanks who was also a musician in his crew until he left her while she was still a child. She was left on the island of Elegia with Gordon, who became her foster parent and supported her dream of starting a "New Era" and later her desire to achieve this dream through a broadcasted, world-wide concert held on Elegia.
Uta's singing voice has been appraised as "otherwordly", enough to grant her the title of the world's greatest diva.
(Source: One Piece Wiki)