Would you trust an algorithm to send someone to jail? Or to diagnose someone with cancer? How about an algorithm that analysed your friendships to calculate if you were reliable enough to take out a loan? In this talk, we’ll go on a tour of the good, the bad and the downright ugly of the algorithms that surround us. We'll examine whether we should rely on algorithms to know what’s best, and ask if we can trust them over our own judgement. We’ll lift the lid on their inner workings, demonstrate their power, expose their limitations, and examine whether they really are an improvement on the humans they are replacing.