Audible free book: http://www.audible.com/computerphile 
How do you use mathematics to help design a computer's user interface? Use Fitts's Law; Dr Sarah Wiseman explains.

CORRECTION - As countless YouTube comments will doubtlessly point out, I said 'Google' when I meant 'PayPal' - mental blip - Apologies! -Sean

Phone Buttons – Numberphile: https://youtu.be/kCSzjExvbTQ 
Upside Down Trees (Huffman Encoding): https://youtu.be/umTbivyJoiI 
Holy Grail of AI: https://youtu.be/tlS5Y2vm02c 
Computer That Changed Everything: https://youtu.be/6LYRgrqJgDc 

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This video was filmed by Brady Haran and edited by Sean Riley.

Computer Science at the University of Nottingham: http://bit.ly/nottscomputer

Computerphile is a sister project to Brady's Numberphile. More at http://www.bradyharan.com