We've all heard of web browser caches, but why does a super fast modern CPU need a cache? Because it's too fast. Dr Steve "Heartbleed" Bagley explains. Professor Steve Furber on Building the BBC Micro: https://www.youtube.com/watch?v=y4WG549i3YY How Computer Memory Works: https://www.youtube.com/watch?v=XETZoRYdtkw Why Asimov's Laws Don't Work: https://www.youtube.com/watch?v=7PKx3kS7f4A The Problem with JPEG: https://www.youtube.com/watch?v=yBX8GFqt6GA http://www.facebook.com/computerphile https://twitter.com/computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: http://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran's Numberphile. More at http://www.bradyharan.com/