Ever wondered why they ask you to write two words during Captcha verification?
Captcha is a program that helps in identifying humans from computers. Many a times you must have noticed that most of the websites ask you to look at some distorted words and type them in a box below. But why do they ask you to type twice, isn't once enough?
Because, in doing so you are helping the digital literary world.
How?
In this new age technological world, every book is being digitalized not only for convenience of reading them on cool gadgets but also with the aim of saving the trees.
But in this technologically enhanced world, there one thing that can never be replaced...human mind. The reason why Captcha is so widely used is because a computer cannot recognize distorted images, therefore automated programs become useless and are unable to generate spam.
Same is the case when physical books are photographically scanned and converted through OCR (Optical Character Recognition) to make them digitally compatible. But this system is not perfect and there are certain words that it can't decipher, therefore by typing the second word we help in digitalizing these words.
Words that OCR cannot read are displayed in reCaptcha box and is deciphered by humans all over the world, after multiple verifications that word is then digitalized. reCaptcha Inc. further explains:
"Each new word that cannot be read correctly by OCR is given to a user in conjunction with another word for which the answer is already known. The user is then asked to read both words. If they solve the one for which the answer is known, the system assumes their answer is correct for the new one. The system then gives the new image to a number of other people to determine with higher confidence, whether the original answer was correct."
reCaptcha system was introduced by Carnegie Mellon University and the company was acquired by Google in 2009. Click here to visit their website.
And click here to learn more stuff from our E-scientist.
Speaking of OCR, there is a totally free online optical character recognition service, and it’s very accurate. I use it all the time:
Rather than forcing your website visitors to decipher warped and distorted text, I prefer the types of captcha that ask them to recognize pictures, like this one: http://demo.confidenttechnologies.com/captcha/