We want to know what you want to see on this channel – leave a comment below or contact us via social media to let us know. We’re listening! http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computerphile is a project by Brady Haran See the full list of Brady’s
Computer
Diffie Hellman has a flaw. Dr Mike Pound explains how a man in the middle could be a big problem, unless we factor it in… Public Key Cryptography: https://youtu.be/GSIDS_lvRv4 Elliptic Curve Cryptography: Coming Soon! https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer
The ‘magic’ trick of pointers to pointers – Professor Brailsford explains how what might seem complicated will actually simplify your code. (See Extra Bits video for a code walkthrough) The Professor’s Code: http://bit.ly/Computerphile_ProfBrails_TripleRef EXTRA BITS – Triple Ref Code: https://youtu.be/1s0w_p5HEuY n.b. Message from the Prof: Many thanks to all of you who have pointed out
We’ve been asking “What’s your favourite (favorite) shortcut key?” as a soundcheck question (this slightly overlapped the “What’s your favourite programming language” question) for the last year. Contributors (in order of appearance) Mike Pound Matt Denton Lorraine Underwood Charles Arthur Rob Miles Adrian Page-Mitchell Derek McAuley Michel Valstar Steven Ceron Stephen Howe Steve Bagley Henry
How does instant messaging encryption protect against attack? Dr Mike Pound on the double ratchet. Diffie Hellman Key Exchange Explained: https://youtu.be/NmM9HA2MQGI Signal Protocol: https://youtu.be/DXv1boalsDI Endianness Explained with an Egg: https://youtu.be/NcaiHcBvDR4 https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister
Surely decimal numbers are easier to understand than binary? So why don’t computers use them? Professor Brailsford explains the relationships between binary, power and simplicity. EXTRA BITS: https://youtu.be/NlWuTYhF8KM Colossus & Bletchley Park: https://youtu.be/9HH-asvLAj4 Inside a Data Centre: https://youtu.be/fd3kSdu4W7c Steve Furber on ARM: https://youtu.be/1jOJl8gRPyQ Fishy Codes – Bletchley’s Other Secret: https://youtu.be/Ou_9ntYRzzw http://www.facebook.com/computerphile Tweets by computer_phile This
How do instant message apps do end to end encryption when one phone may not even be switched on yet? Dr Mike Pound on the Signal protocol at the core of most messaging apps. Double Ratchet: COMING SOON! https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the
Hear Brian Kernighan on how he got into programming, the successors of C and the biggest challenges… Watch Part 2 before it’s live!: https://youtu.be/VVpRj3Po6K4 https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran’s Numberphile. More
Summing up why Hamming’s error correcting codes are regarded as ‘Perfect’ – Professor Brailsford explains. EXTRA BITS: https://youtu.be/i4zC67Yf5Iw For more background on this: https://youtu.be/1_X-7BgHbE0 http://www.facebook.com/computerphile Tweets by 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
Negative Binary Numbers – you may have heard of ‘signed’ numbers, but do you know how they work? Professor Brailsford explains not just how, but why we use the systems we do. Binary Addition: http://youtu.be/WN8i5cwjkSE Most Difficult Program to Compute?: http://youtu.be/i7sm9dzFtEI Floating Point Numbers: http://youtu.be/PZRI1IfStY0 http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited
ISPs don’t always get it right – they gamble that all of their subscribers won’t use all of their bandwidth all of the time. Dr Richard Mortier explains Statistical Multiplexing. Routing & YouTube Offline: http://youtu.be/AkxqkoxErRk Network Stacks & The Internet: http://youtu.be/PG9oKZdFb7w Punch Card Programming: http://youtu.be/KG2M4ttzBnY Undecidability Series: http://www.youtube.com/playlist?list=PLzH6n4zXuckpIQPv8hiHpJkSyv0fmXEYr http://www.facebook.com/computerphile Tweets by computer_phile This video was
Removing voxels until the shape emerges. Space Carving is a kind of virtual sculpture. Image Analyst Dr Mike Pound explains how though it’s a bit rough and ready, it can be lightning fast. Rob Miles on Game Playing AI: https://youtu.be/5oXyibEgJr0 Deep Learning: https://youtu.be/l42lr8AlrHk Secure Web Browsing: https://www.youtube.com/watch?v=E_wX40fQwEA Thanks to Rick van de Zedde, Wageningen UR
One of the cleanest ways to cut down a search space when working out point proximity! Mike Pound explains K-Dimension Trees. EXTRA BITS: https://youtu.be/uP20LhbHFBo https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran’s Numberphile. More
How do you pick a secure password that’s memorable but truly random? Dr Mike Pound explains Diceware The Diceware website: http://bit.ly/c_diceware (Diceware is a trademark of A G Reinhold) Another great thing to do with dice is play games 🙂 -Sean Password Cracking: https://youtu.be/7U-RbOKanYs How to Choose a Password: https://youtu.be/3NjQ9b3pgIg https://www.facebook.com/computerphile Tweets by computer_phile This
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://youtu.be/y4WG549i3YY How Computer Memory Works: https://youtu.be/XETZoRYdtkw Why Asimov’s Laws Don’t Work: https://youtu.be/7PKx3kS7f4A The Problem with JPEG: https://youtu.be/yBX8GFqt6GA http://www.facebook.com/computerphile Tweets by
Websites can still be hacked using SQL injection – Tom explains how sites written in PHP (and other languages too) can be vulnerable and have basic security issues. More from Tom Scott: http://www.youtube.com/user/enyay and https://twitter.com/tomscott Follow the Cookie Trail: http://www.youtube.com/watch?v=LHSSY8QNvew CERN Computing Centre & Mouse Farm: http://www.youtube.com/watch?v=S0MgJFGL5jg http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed
Taking edges one step further with Hysteresis Thresholding – The Canny Operator explained by Image Analyst Dr Mike Pound Finding the Edges (Sobel Operator): https://youtu.be/uihBwtPIBxM How Blurs & Filters work: https://youtu.be/C_zFhWdM4ic Why Asimov’s Three Laws Don’t Work: https://youtu.be/7PKx3kS7f4A Geometric Face Recognition: https://youtu.be/BCBZPtZCI7w http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley.
What was the first undecidable problem? Professor Brailsford takes us on a computerphile tangent & gives us his angle on a pre-computer example of undecidability. Note from Professor Brailsford: a couple of corrections for this film: 1/ “… early 18th Century” for Gauss should be ” … early 19th century” 2/ “… 100 years ago”
If you’ve wondered how computer scientists use pairs of cameras to reconstruct a 3D scene, Image Analyst & Lecturer Dr Mike Pound explains. EXTRA BITS: https://www.youtube.com/watch?v=g3bKLcYGhOg Industrial Light-Field Magic: https://youtu.be/ZIfn2Ocy9RU Brain Scanner: https://youtu.be/TQ0sL1ZGnQ4 3D Rock Art Scanner: https://youtu.be/Ahdnkj77rAY CPU vs GPU: https://youtu.be/_cyVDoyI6NE http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley.
XOR, an essential logic operation, explained by Professor Brailsford. Continues our series on logic gates/operations. AND OR NOT – Logic Gates Explained: https://youtu.be/UvI-AMAtrvE Binary Addition & Overflow: https://youtu.be/WN8i5cwjkSE Capturing Digital Images (The Bayer Filter) : https://youtu.be/LWxu4rkZBLw Flip Flops, Latches & Memory Details: https://youtu.be/-Ecf7lb4aZ0 The Virtual Reality Cave: https://youtu.be/STMcWUtQr1Y XOR Easter Egg: http://youtu.be/e3JYeJke7KI The Professor’s Notes:
We look at where the ubiquitous AES came from. Dr Mike Pound introduces the Rijndael algorithm. SP Networks: https://youtu.be/DLjzI5dX8jc How AES Works: https://youtu.be/O4xNJsjtN6E https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran’s Numberphile. More at
We look at and run the code that exploits the Heartbleed bug. Dr. Steven Bagley takes us through the code and shows us how it works. Relevant RFC Document: http://bit.ly/heartbleed-rfc Domino Addition: http://youtu.be/lNuPy-r1GuQ YouTube’s Secret Algorithm: http://youtu.be/BsCeNCVb-d8 http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University
Secure Hashing Algorithm (SHA1) explained. Dr Mike Pound explains how files are used to generate seemingly random hash strings. EXTRA BITS: https://youtu.be/f8ZP_1K2Y-U Tom Scott on Hash Algorithms: https://youtu.be/b4b8ktEV4Bg http://www.facebook.com/computerphile Tweets by 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
Where are we at with Quantum computing? Robert Smith (of Rigetti Computing) explains that we’re in the EDSAC/ENIAC era…. see follow up video for more technical information: Watch the next one in the series: https://youtu.be/ZN0lhYU1f5Q https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham:
When a Bitcoin Miner Mines, what is happening? Dr Mike Pound exposes the process.. note: at 3:39 Mike mentions a Bitcoin is mined every ten minutes when it is actually a block that is mined every ten minutes, at time of recording a successful block generates 12.5 new Bitcoins. Password Cracking: https://youtu.be/7U-RbOKanYs Onion Routing (TOR):
Machine Learning where you put in a fraction of the effort? What’s not to like? – Dr Michel Valstar explains Active & Cooperative Learning. https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran’s Numberphile. More
The story of recursion continues as Professor Brailsford explains one of the most difficult programs to compute: Ackermann’s function. Professor Brailsford’s programs: http://bit.ly/1nhKtW4 Follow Up Film from the Prof in response to this film: https://www.youtube.com/watch?v=uNACwX-O5lk What on Earth is Recursion?: http://youtu.be/Mv9NEXX1VHc Fibonacci Programming: http://youtu.be/7t_pTlH9HwA Heartbleed, Running the Code: http://youtu.be/1dOCHwf8zVQ VR Series: COMING SOON! Please note,
Colossus was one of the very first electronic, special purpose, computers and it was created almost two years earlier than the better known ENIAC. We visit Bletchley Park, home of the code breakers, and TNMoC, The National Museum of Computing. Professor Brailsford shows us the Colossus replica. The Most Difficult Program to Compute?: https://youtu.be/i7sm9dzFtEI Computer
Why encrypted group messaging isn’t as secure as point to point. Dr Mike Pound explains this ongoing problem. Instant Messaging & the Signal Protocol: https://youtu.be/DXv1boalsDI Double Ratchet Messaging Encryption: https://youtu.be/9sO2qdTci-s Relevant paper: https://eprint.iacr.org/2017/666.pdf https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile
Image filters make most people think of Instagram or Camera Phone apps, but what’s really going on at pixel level? Image Analyst Dr Mike Pound explains some of the most common filters. Secrets Hidden in Images (Steganography): https://youtu.be/TWEXCYQKyDc JPEG ‘files’ & Colour: https://youtu.be/n_uNPbdenRs The Dress: https://youtu.be/Tw0PlGpaqy4 The VR Cave: https://youtu.be/STMcWUtQr1Y JPEG Discrete Cosine Transform (DCT):
The basis of almost all functional programming, Professor Graham Hutton explains Lambda Calculus. http://www.facebook.com/computerphile Tweets by 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
Connecting via SSH to a remote machine is second nature to some, but how does it work? Dr Steve Bagley. Dr Mike Pound on Hashing (mentions padding but full video on padding is planned to follow): https://youtu.be/DMtFhACPnTY https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University
Audible free book: http://www.audible.com/computerphile DoS or Denial of Service Attacks are one thing, but Amplified Denial of Service Attacks could threaten the internet itself. Tom Scott explains what they are. More from Tom Scott: http://www.youtube.com/user/enyay and https://twitter.com/tomscott http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computerphile is a sister project
End to end encryption, government ministers are again talking about stopping it. What is it and why might that be a bad idea? Dr Mike Pound explains. Hololens: https://youtu.be/gp8UiYOw8Fc Blockchain: https://youtu.be/qcuc3rgwZAE http://www.facebook.com/computerphile Tweets by 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
What goes on TOR stays on TOR, or so we hope. Dr Mike Pound takes us through how Onion Routing works. This video was formerly called “Onion Routing” EXTRA BITS: https://youtu.be/6eWkdyRNfqY End to End Encryption: https://youtu.be/jkV1KEJGKRA Deep Web / Dark Web: https://youtu.be/joxQ_XbsPVw http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley.
Alan Turing almost accidentally created the blueprint for the modern day digital computer. Here Mark Jago takes us through The Halting Problem. Turing Machines Explained: https://youtu.be/dNRDvLACg5Q Busy Beaver: https://youtu.be/CE8UhcyJS0I VR Simulator: http://youtu.be/Lm0lA0enPSk What on Earth is Recursion?: http://youtu.be/Mv9NEXX1VHc Thanks to Assistant Professor Mark Jago of the University of Nottingham. http://www.facebook.com/computerphile Tweets by computer_phile This video
Audible Free Book: http://www.audible.com/computerphile Recursion; like something from the film “Inception”. Even Professor Brailsford says it can be hard to get your head around – watch him make it much easier to understand… EXTRA BITS: http://youtu.be/0pncNKHj-Sc Opening up the Original Mac: http://youtu.be/wFJrHuSXnZM http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley.
Password1 is a terrible password, but how can I remember different secure passwords for each login? Use a password manager. Dr Mike Pound explains how they work. How to Choose a Password: https://www.youtube.com/watch?v=3NjQ9b3pgIg Password Cracking on a 4x Titan X Beast: https://youtu.be/7U-RbOKanYs Securing Stream Ciphers (HMAC): https://www.youtube.com/watch?v=wlSG3pEiQdc https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed
Should Apple unlock a terrorists iPhone for the FBI? Professor Ross Anderson explains how this is a “Pandora’s Box” situation. Buffer Overflow Attacks: https://youtu.be/1S0aBV-Waeo $5 Computer: https://youtu.be/WR0ghM3U0M4 AI Safety: https://youtu.be/IB1OvoCNnWY EXTRA BITS: https://youtu.be/6iGxNku7ilw http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: http://bit.ly/nottscomputer Computerphile
How do digital cameras turn light into the data that computers can handle? In this second part of our computer vision series, Image Analyst Mike Pound explains the Bayer Filter. Professor Steve Furber on the BBC Micro: https://youtu.be/y4WG549i3YY 2D Images: http://youtu.be/06OHflWNCOE Universe of Triangles: http://youtu.be/KdyvizaygyY?list=PLzH6n4zXuckrPkEUK5iMQrQyvj9Z6WCrm Pushing the Atari Limits: http://youtu.be/3OdtfsXOkEY http://www.facebook.com/computerphile Tweets by computer_phile This
Before laser-printers, high quality print-outs were the domain of typesetters, expensive and tightly controlled. In 1979 a Bell Labs team reverse engineered one in their summer vacation. Professor Brailsford has the details. EXTRA BITS – More on Printing and Typesetting History: https://www.youtube.com/watch?v=HdModNEK_1U Mainframes and the Unix Revolution: http://youtu.be/-rPPqm44xLs To find out how the 1980 Bell
Just what are elliptic curves and why use a graph shape in cryptography? Dr Mike Pound explains. Mike’s myriad Diffie-Hellman videos: https://www.youtube.com/playlist?list=PLzH6n4zXuckpoaxDKOOV26yhgoY2S-xYg https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran’s Numberphile. More at http://www.bradyharan.com
Dijkstra’s Algorithm finds the shortest path between two points. Dr Mike Pound explains how it works. How Sat Nav Works: https://youtu.be/EUrU1y5is3Y Slow Loris Attack: https://youtu.be/XiFkyR35v2Y http://www.facebook.com/computerphile Tweets by 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.
Audible free book: http://www.audible.com/computerphile Hashing Algorithms are used to ensure file authenticity, but how secure are they and why do they keep changing? Tom Scott hashes it out. More from Tom Scott: http://www.youtube.com/user/enyay and https://twitter.com/tomscott http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Pigeon Sound Effects courtesy of http://www.freesfx.co.uk/ Computerphile
How do websites marry up to their IP addresses? Dr Mike Pound explains the Domain Name System – DNS. https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran’s Numberphile. More at http://www.bradyharan.com