If we're honest, we didn't really know who Demi Lovato was at all. But that's because we don't eat hot dogs, shoot guns and drive monster trucks – or, if you want to use the scientific term, because we aren't American.
Demi Lovato is BIG in America. Not like Lady Gaga big, obvo, or you'd have heard of her. Like moderately huge to massive, roughly. Her albums – she's had three, she's a singer, keep up – have all done pretty well, and her last one (Unbroken) hit number four in the charts. And yet you have no idea who she is.
Demi Lovato performs on stage
Bonus fact: She looks a bit like Demi Moore in this picture
Let us educate you, then, with a string of poorly-selected facts to tie in with these pictures of her in concert from yesterday! Firstly: Demi Lovato used to act alongside Barney the Dinosaur – not in his critically-acclaimed 1974 performance of Pinter's The Dumb Waiter, but in the TV show that he did for kids in the nineties. 
Secondly: Her most recent single, Skyscraper, reached number ten in the US singles chart and is one of the more inspirational songs we've heard come out of the pop scene in recent years. According to the YouTube comments on the video we estimate it's responsible for the avoidance of one in four teenage suicides over the last year.
Thirdly: She once punched a backing dancer for the Jonas Brothers in the face whilst in mid-air. Not that she performed a flying thunder punch, or anything – she was in a plane at the time (as was the backing dancer, although if he wasn't, this would be a much more exciting fact).
Demi Lovato in concert
Especially if Demi was flying the plane at the time
And, finally: Demi Lovato is 19 years old, but has already checked into rehab – the punching incident sealed the deal – but she's out, now, and apparently fine. Which is kind of impressive. We've only once had to have A Bit Of A Think About How Much We're Drinking coupled with Frowny Eyebrows From Our Doctor Accompanied By Vague Promises, and we've got at least five years on her.
There. Your Demi Lovato knowledge is complete. Well, as complete as we're going to make it, anyway.