Stage names in Hollywood are fairly common. Whether it's to simplify a more complicated birth name (because the general public is too lazy to learn it) or to take on an entirely new identity, the moniker by which you may know a certain celebrity might not have been the name with which he or she was born.

Most people are aware that, yes, Madonna does have a last name, you probably don't know what it is. Also, did you have any clue Oprah was originally named Orpah? That's not a typo: She was named after a Biblical character who appears in the Book of Ruth, but her name was incorrectly read as Oprah so many times that she decided to embrace the mispronunciation and go by Oprah forever.

Some celebrities invented entirely new names: Lana Del Rey was once Elizabeth "Lizzy" Grant and Bruno Mars was born with the name Peter Gene Hernandez. (Wow.) Calvin Harris, meanwhile, was born with the name Adam Richard Wiles, while Nina Dobrev was actually born Nikolina Konstantinova Dobreva.

Other celebs simply shortened a part of their names into a nickname more suited for their public personas, a la Fergie (originally born Stacy Ann Ferguson) and Kesha, who pulled a Madonna...but was born Kesha Rose Sebert.

We compiled a list of 50 celebrities who go by a different name than what they were given at birth — at least in the public eye. Check out the gallery below to find out how your faves changed their names.