To celebrate Robert Moog’s 78th Birthday, Google published on May 23, 2012 an interactive doodle of the electronic analog Moog Synthesizer.
Google Doodle : Moog Synthesizer
The Moog doodle was created by Google engineers Reinaldo Aguiar and Rui Lopes and the doodle team lead Ryan Germick.
For Alan Turing’s Centennial, Google published one month later (June 23, 2012) an interactive doodle showing a Turing Machine. The doodle was designed by Jered Wierzbicki and Corrie Scalisi, Software Engineers, and by Doodler Sophia Foster-Dimino. The code for this doodle was open sourced and is available at Google Code.
Google Doodle : Turing Machine
A video about the Art & Technology behind Google Doodles is available at Youtube.
CAPTCHA is standing for “Completely Automated Public Turing test to tell Computers and Humans Apart”. It is a type of challenge-response test used in computing as an attempt to ensure that the response is generated by a person. Because other computers are supposedly unable to solve the CAPTCHA, it is sometimes described as a reverse Turing test, because it is administered by a machine and targeted to a human.
A common type of CAPTCHA requires the user to type letters or digits from a distorted image that appears on the screen.
The term “CAPTCHA” was launched in 2000 by Luis von Ahn, Manuel Blum, Nicholas J. Hopper, and John Langford (all of Carnegie Mellon University).
A very interesting contribution about CAPTCHA (in french) has been published by Nicolas Kerschenbaum, a security consultant of the french company Xmco Partners.