Google Doodle June 23: 2012 

Tribute to Alan Turing 

 Mathematician and computer scientist Alan Turing, born 100 years ago, on June 23, 1912, created a device aptly named the Turing machine. The Turing machine which was an idealized model for math calculations according to Wolfram MathWorld. 

He published a paper,“On Computable Numbers” (PDF) introducing two concepts, algorithms and computing machines that helped pave the way for modern computers.

The Google Doodle for 6/23/12 features six interactive puzzles. These sites help you solve the puzzle, if you get stuck.

 How to solve the Google Doodle
Alan Turing Google Logo Puzzle