We all have a list of our favourite celebrities and love it when we see them on the street.
We're all prone to fan-girl moments (yeah we know you do it too dudes!), but if you try calling these stars in the street, they may not answer you because you wouldn't actually be calling them by their real names!
Most people don't go by their birth names in show business and create stage names for themselves to keep their true identities hidden, but we've found out the real names of a few celebs and you'll probably understand the changes after you see them.
We have all seen Olivia Wilde in the O.C and Cowboys and Aliens, but did you know that Wilde is actually not her real last name? The actresses' actual surname is Cockburn but she changed it to Wilde as a tribute to the British writer Oscar Wilde when she started acting.
Jamie Foxx has been in a lot of great movies of late, but we'll never forget his track 'Gold Digger' with Kanye West because it's such a great karaoke song. You probably shouldn't forget his real name, Eric Marlon Bishop, either. He apparently changed his name to sound like a woman's!
Joaquin Phoenix changed his name too. The skillful actor decided to change his last name to Phoenix from Bottom. Yeah, we would have too.
Elton John is royally flamboyant. His real name is also quite regal, so you would be forgiven for thinking that Reginald Dwight was a prince instead of the 'Tiny Dancer' singer.
Nice to meet you Reginald!
Images: Glamour, Huffington Post, Today, Annapurna Pictures