It's no secret that most artists DON'T write their own songs. In fact, its rare nowadays to source a successful yet credible track that was actually self-penned.
There's also a lot of hits out there with rather well-known ghostwriters behind them. BBC 1Xtra claims up to 40% of rap lyrics aren't self-written, but that's not the only genre guilty of it. We've compiled a list of some of the most famous faces behind the biggest hits - find out which other rapper actually wrote 'Still Dre', as well as the UK singer behind a very patriotic Miley Cyrus hit.