It's absolutely everywhere, but what is TLS and where did it come from? Dr Mike Pound explains the background behind this ubiquitous Internet security protocol. Heartbleed, Running the Code: Secure Web Browsing: Network Stacks & The Internet: This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: Computerphile is a sister project to Brady Haran's Numberphile. More at