Like many I was impressed with notch's JavaScript demo at http://jsfiddle.net/uzMPU/ so I dug into how his texture generator actually does its thing.
I must stress this is non-rehearsed, one take, so apologies for verbosity and any inaccuracies. Please leave comments correcting any mistakes for the benefit of future viewers. And if you're a JavaScript or gamedev expert, this video may not be for you! :)
And wouldn't you know.. 0x966c4a really is brown - http://www.color-hex.com/color/966c4a ;-) Oops!
Watch video How Notch's JS Experiment Generates Its Textures in Code online without registration, duration hours minute second in high quality. This video was added by user Peter Cooper 02 December 2012, don't forget to share it with your friends and acquaintances, it has been viewed on our site 44,645 once and liked it 578 people.