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
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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
How do we exchange a secret key in the clear? Spoiler: We don’t – Dr Mike Pound shows us exactly what happens. Mathematics bit: https://youtu.be/Yjrfm_oRO0w Computing Limit: https://youtu.be/jv2H9fp9dT8 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
Bit flipping a stream cipher could help you hit the Jackpot! But not with HMAC. Dr Mike Pound explains. Correction : “pseudo” is spelled incorrectly on the graphic. 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
JPEG Isn’t a file format. Image Analyst Mike Pound explains why not in our first in a series about how JPEG works. Colourspaces: https://youtu.be/LFXN9PiOGtY Elegant Compression (The LZ Method): https://youtu.be/goOa3DGezUA Capturing Digital Images (The Bayer Filter): https://youtu.be/LWxu4rkZBLw Discrete Cosine Transform: https://youtu.be/Q2aEzeMDHMA http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer
The danger of assuming general artificial intelligence will be the same as human intelligence. Rob Miles explains with a simple example: The deadly stamp collector. The Problem with JPEG: https://youtu.be/yBX8GFqt6GA Apple’s $200,000 Computer: https://youtu.be/PccvZRTUhbI Rabbits, Faces & Hyperspaces: https://youtu.be/q6iqI2GIllI Thanks to Nottingham Hackspace for the location. http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and
Commonly used grep was written overnight, but why and how did it get its name? Professor Brian Kernighan explains. EXTRA BITS: https://youtu.be/bSaBe6WiC2s Inside an ALT Coin Mining Operation: COMING SOON Unix Pipeline: https://youtu.be/bKzonnwoR2I 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
Audible free book: http://www.audible.com/computerphile Representing symbols, characters and letters that are used worldwide is no mean feat, but unicode managed it – how? Tom Scott explains how the web has settled on a standard. More from Tom Scott: http://www.youtube.com/user/enyay and https://twitter.com/tomscott EXTRA BITS: http://youtu.be/qBex3IDaUbU Data Security: http://youtu.be/4SSSMi4X_mA http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed
Audible free book: http://www.audible.com/computerphile Catering for a global audience is difficult, Tom takes us through a ‘timezones’ style explanation of the things you need to keep in mind when internationalising your code. This video features Tom Scott – more from him at: http://www.youtube.com/enyay & https://twitter.com/tomscott The Problem with Time & Timezones: http://youtu.be/-5wpm-gesOY Emoji & the
Quick Sort is a popular sorting algorithm, but how does it work? Alex continues our exploration of sorting algorithms with a quick look at quick sort. Original ‘get sorted’ film: http://youtu.be/kgBjXUE_Nwc Cookies: http://youtu.be/LHSSY8QNvew Alex’s code that generated the data for the tests on the original ‘get sorted’ video: https://github.com/apinkney97/Sorts Alex’s graph of all the results
Security of users’ passwords should be at the forefront of every web developer’s mind. Tom takes us through the insecure ways in which some websites deal with passwords. Note: At circa 8mins, the animation does not show how the ‘salt’ is also stored in the database alongside the username. Hashing Algorithms and Security: http://youtu.be/b4b8ktEV4Bg Security
For the past year, we’ve been asking this as a sound-check question. Here are the results! Professor Graham Hutton (Haskell) Joseph Best (BBC Basic) David CX (Java / Python) Lorraine Underwood (PHP) Rob Miles (Python) Charles Arthur (Python) Sarah Spencer (Javascript) Matt Denton (C) Matt Lloyd (C/Python/PHP) Ian Dickinson (C) Tom Sheridan (Python) Spencer Owen
If you don’t secure your web forms, one mistaken click could be all it takes for your users to delete their own accounts. Tom Scott explains. http://www.facebook.com/computerphile Tweets by computer_phile More from Tom Scott: http://www.youtube.com/user/enyay and https://twitter.com/tomscott Hacking Websites with SQL Injection: http://www.youtube.com/watch?v=_jKylhJtPmI Cracking Websites with Cross Site Scripting: http://www.youtube.com/watch?v=L5l9lSnNMxg This video was filmed and
Audible free book: http://www.audible.com/computerphile JavaScript is dangerous! Why? How are websites vulnerable to it? Find out about bug-bounties from Tom Scott. 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 to Brady Haran’s Numberphile. See the full list of
A web app that works out how many seconds ago something happened. How hard can coding that be? Tom Scott explains how time twists and turns like a twisty-turny thing. It’s not to be trifled with! A Universe of Triangles: http://www.youtube.com/watch?v=KdyvizaygyY LZ Compression in Text: http://www.youtube.com/watch?v=goOa3DGezUA Characters, Symbols and the Unicode Miracle: http://www.youtube.com/watch?v=MijmeoH9LT4 More from
Why can’t floating point do money? It’s a brilliant solution for speed of calculations in the computer, but how and why does moving the decimal point (well, in this case binary or radix point) help and how does it get currency so wrong? 3D Graphics Playlist: http://www.youtube.com/playlist?list=PLzH6n4zXuckrPkEUK5iMQrQyvj9Z6WCrm The Trouble with Timezones: http://youtu.be/-5wpm-gesOY More from Tom
Spies used to meet in the park to exchange code words, now things have moved on – Robert Miles explains the principle of Public/Private Key Cryptography note1: Yes, it should have been ‘Obi Wan’ not ‘Obi One’ 🙂 note2: The string of ‘garbage’ text in the two examples should have been different to illustrate more
What does it mean for something to be Turing Complete? Professor Brailsford explains. Turing Machine Primer: https://youtu.be/DILF8usqp7M Turing Machines Explained: https://youtu.be/dNRDvLACg5Q Chomsky Hierarchy: https://youtu.be/224plb3bCog What on Earth is Recursion?: https://youtu.be/Mv9NEXX1VHc 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
We’ve all got to the edge of the wifi coverage, but the idea of coverage produces a network problem, the Hidden Node Problem. Dr Steve Bagley explains. 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
Never use JPEG with text. But why? Image Analyst Mike Pound explains what goes wrong when JPEG tries to compress text. Holy Grail of AI: https://youtu.be/tlS5Y2vm02c Computer That Changed Everything: https://youtu.be/6LYRgrqJgDc Arduino Hardware: https://youtu.be/b4z1zkmo1BE How JPEG Works: https://www.youtube.com/playlist?list=PLzH6n4zXuckoAod3z31QEST1ZaizBuNHh http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the
Turing Machines are the basis of modern computing, but what actually is a Turing Machine? Assistant Professor Mark Jago explains. Turing & The Halting Problem: http://youtu.be/macM_MtS_w4 Busy Beavers: https://youtu.be/CE8UhcyJS0I Avatars & In-Flight VR: http://youtu.be/TLKqKlrQv4s The (pink) VR Simulator: http://youtu.be/Lm0lA0enPSk http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at
Just what was it that took Facebook, Instagram & WhatsApp offline on 4th October 2021? – Dr Steve Bagley investigates! previously titled “Facebook’s Day Off” Facebook announcement on the outage: https://bit.ly/C_FB-Outage The visualisation software Steve was using was BGP play, downloaded from the RIPE website. https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited
This Primer is to accompany the ‘Busy Beaver Turing Machines’ film which can be viewed here: http://youtu.be/CE8UhcyJS0I Professor Brailsford’s code and further reading: http://bit.ly/busybeaver Turing and the Halting Problem: http://youtu.be/macM_MtS_w4 Busy Beaver Turing Machines: http://youtu.be/CE8UhcyJS0I Domino Addition – Numberphile: http://youtu.be/lNuPy-r1GuQ Ackermann Follow Up: http://youtu.be/uNACwX-O5lk ‘Turing Machines Collection’ Playlist: http://www.youtube.com/playlist?list=PLzH6n4zXuckrEzV0CB1xXbSdsP_a7VUoK “The Most Difficult Program to Compute?”
Postscript took off like a rocket but PDF took its time, many people wondering “What’s it for?” Professor Brailsford’s experience with one such person – a US immigration officer… Unrolling the Loops (Postscript/PDF intro): https://youtu.be/guXgBe2wvEA Fire Pong in Detail: https://youtu.be/ZoZMMg1r_Oc Deep Dream: https://youtu.be/BsSmBPmPeYQ FPS & Digital Video: https://youtu.be/yniSnYtkrwQ Password Cracking: https://youtu.be/7U-RbOKanYs http://www.facebook.com/computerphile Tweets by computer_phile
10% off at Squarespace: http://squarespace.com/computerphile Secret services want to read people’s communications, politicians talk about terrorists, but what’s the reality of banning encryption? Ross Anderson, Professor of Security Engineering at the Computer Laboratory, University of Cambridge explains how history repeats itself. The Dress: https://youtu.be/Tw0PlGpaqy4 The VR Cave: https://youtu.be/STMcWUtQr1Y Public Key Cryptography: https://youtu.be/GSIDS_lvRv4 Alan Turing and
Our eyes can spot edges with no problems, but how do computers determine what’s an edge and what’s not? Image Analyst Dr Mike Pound explains the Sobel Edge detector. How Blurs & Filters work: https://youtu.be/C_zFhWdM4ic The Problem with JPEG: https://youtu.be/yBX8GFqt6GA Secrets Hidden in Images (Steganography): https://youtu.be/TWEXCYQKyDc Man in the Middle Attacks: https://youtu.be/-enHfpHMBo4 Mike’s Code in
Harry’s: http://www.harrys.com/ use coupon code “COMPUTERPHILE” for $5 off What’s a colourspace and why do we have different ones? It’s horses for courses as Image Analyst Mike Pound explains. Digital Images: https://www.youtube.com/playlist?list=PLzH6n4zXuckpbNdFO2WW78evpMBqgqyp8 Atari ST: Pushing the Limits: https://youtu.be/3OdtfsXOkEY Professor Steve Furber on ARM: COMING SOON! Universe of Triangles: https://www.youtube.com/playlist?list=PLzH6n4zXuckrPkEUK5iMQrQyvj9Z6WCrm http://www.facebook.com/computerphile Tweets by computer_phile This video
Over Computerphile’s first year, we asked each contributor the question: “Mac or PC?” as part of our sound-check. Here are the answers… nb – we know that PC is defined as Personal Computer, and that to be pedantic, a Mac ‘is’ a PC, but in general, ‘PC’ is the way people refer to a machine
They’re called ‘Finite State Automata” and occupy the centre of Chomsky’s Hierarchy – Professor Brailsford explains the ultimate single purpose computer. Note: Professor Brailsford omitted the transition from the 5 state to 25 state by means of a 20p, he has amended the linked notes! Chomsky’s Hierarchy: https://youtu.be/224plb3bCog $5 Computer – Raspberry Pi Zero: https://youtu.be/WR0ghM3U0M4