The history of the Taquin aka Fifteen puzzle, invented by Noyes Palmer Chapman and made popular by Sam Loyd: http://en.wikipedia.org/wiki/Fifteen_puzzle

The W3Schools website, a reference for all web technologies: http://www.w3schools.com/

The excellent open-source and cross-browser Javascript library jQuery: http://jquery.com/

The Alsacréations website, providing lots of very good tutorials: http://www.alsacreations.com/ (in French)

The history of Lenna (aka Lena), or how a picture (taken by photographer Dwight Hooker) from the November 1972 Playboy magazine has become the industrial standard test image for image processing algorithms: http://en.wikipedia.org/wiki/Lenna http://www.lenna.org/