Elvis: Believe it or not, The King had almost nothing to do with the writing of his own songs. 'Hound Dog', 'Jailhouse Rock' and 'Suspicious Minds' were all written by other people. Elvis had the occasional co-writer credit, but not often

Katy Perry - By contrast katy Perry had a hand in writing every song she's put out, including her first album of Christian rock. Perry's brand of wacko sweet shop pop is all her own.

Diana Ross - With The Supremes and as a solo artist, Diana Ross is one of the most iconic vocalists to ever hold a mic. But she isn't responsible for the words she sings, having virtually nothing to do with the songwriting

Marina & The Diamonds - One the other hand plucky pop starlet Marina Diamandis wrote or co-wrote every song on her two albums.

Frank Sinatra - It was fairly common for singers at the time to have songs written for them, but it might still come as a shock to some that Ol' Blues Eyes had nothing to do with the writing of his songs.

The Jonas Brothers - Boyband-with-guitars and stars of Camp Rock The Jonas Brothers have written or co-written nearly every song on their four studio albums. There's a fifth supposed to arrive later this year. Get excited.

Elton John - Elton's responsible for the music to his songs - the piano parts are all his own - but the lyrics are often the work of professional partner, Bernie Taupin. Touching tribute to Princess Diana 'Candle In The Wind'? Not Elton's words.

McFly - It can be hard to tell how much pop band there is to McFly, with the band trying to portray themselves as the real deal despite their manufactured origins. But they do write their own songs, so that's something to their credit. The quality of their songs is perhaps another matter.

Whitney Houston - The late, great Whitney Houston might've been one of the greatest singers in living memory, but she owes a whole host of songwriters for providing her with the words.

Ke$ha - Whatever you think of Ke$ha's music, it is her music. Kesha Sebert has a co-writing credit on every song on her albums Animal, Cannibal and Warrior. As much as she might wish someone else had forced the words to 'Die Young' on her, they didn't.

Marvin Gaye - Marvin gave us some of the most recognisable and touching piece of soul and Motown music ever. 'Heard It Through The Grapevine' is instantly recognisable for his voice as much as the slinky bass that introduces it. But it wasn't written by Gaye, nor was the vast majority of his recorded material.

Demi Lovato - Rising through the Disney ranks and having served her time at Camp Rock, Lovato is now a proper singer. Apparently. She can back this claim up with the fact that she co-wrote the vast majority of her recorded material. And a lot of her debut album Don't Forget was written with (would you believe it?) The Jonas Brothers.