How do we know if racism really exists? And, if it does, how big a problem is it for the outcomes of people of colour? Only science has the answers to some of society's most pressing questions.

Hillary Rodham Clinton is the first woman to be nominated for president by a major political party and the winner of the national popular vote. She served as Secretary of State after nearly four decades in public service as an attorney, First Lady, and US Senator. She is married to former US President Bill Clinton and is a mother and grandmother. Visit HillaryClinton.com.

'People say to me, if you could do it all again, knowing what you know now, would you change anything? I'm like, f*** no. If I'd been clean and sober, I wouldn't be Ozzy. If I'd done normal, sensible things, I wouldn't be Ozzy.

Look, if it ends tomorrow, I can't complain. I've been all around the world. Seen a lot of things. I've done good... and I've done bad. But right now, I'm not ready to go anywhere.'

At the age of sixty-nine, Ozzy Osbourne was on a triumpha...

The UK's top-selling true crime writer and author of the #1 bestselling The Suspicions of Mr Whicher takes on the notorious murders at 10 Rillington Place

Tony Blair learnt the precepts of governing the hard way: by leading a country for over ten years. In that time he came to understand that there are certain key characteristics of successful government that he wished he had known about when he started.