CAPTCHA

With the advent of the computer age, a strange new language pattern has started emerging. It has been made worse with the rampant messages sent across in incredible speeds through cellular phones. Sometime back when I logged in into a site I was asked to decipher a set of contorted letters given in a small box. The first time I did it I went wrong. The letters were not only contorted but were also beyond recognition. The website was kind enough to give me another chance. In the second chance the words were contorted but were more recognizable. I then came to know that it was called CAPTCHA. At the first look I thought it was a portmanteau word formed out of combining Captain and the Hindi word for uncle –chacha !! Some googling threw light on the word.

CAPTCHA is infact an acronym of Completely Automated Public Turing Test* To TellComputers and Humans Apart. A distorted image of letters and numbers used to ensure that a response is not generated by a computer, in order to prevent spamming.

(*Turing Test is a test of a machine's ability to demonstrate intelligence.)

Wikipedia explains: http://en.wikipedia.org/wiki/CAPTCHA

A CAPTCHA or Captcha (pronounced /ˈkæptʃə/) is a type of challenge-response test used incomputing as an attempt to ensure that the response is not generated by a computer. The process usually involves one computer (a server) asking a user to complete a simple test which the computer is able to generate and grade. Because other computers are supposedly unable to solve the CAPTCHA, any user entering a correct solution is presumed to be human. Thus, it is sometimes described as a reverse Turing test, because it is administered by a machine and targeted to a human, in contrast to the standard Turing test that is typically administered by a human and targeted to a machine. 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 coined in 2000 by Luis von Ahn, Manuel Blum, Nicholas J. Hopper, and John Langford (all of Carnegie Mellon University). It is a contrived acronym based on the word "capture" and standing for "Completely Automated Public Turing test to tell Computers and Humans Apart". Carnegie Mellon University attempted to trademark the term, but the trademark application was abandoned on 21 April 2008.

This is how the Captcha words look like. It looks like they have kept it to be difficult so that we win over the computer !!! As a layman I am happy that humans continue to be more intelligent than the computer.

P.Uday Shankar.