What is CAPTCHA? All Things You Should Know About CAPTCHA

I think you all are familiar with the captcha. One time at least we all have face the captcha. But do you ever think why it is compulsory to solve the captcha? And some other questions like what is CAPTCHA? Why we use it? how it works. So if you want the answers to all the questions then you are at right place.

Make sure you read the whole article to get the full knowledge about captcha and Recaptcha. Before going into the further discussion, you must know what is CAPTCHA.



CAPTCHA stands for Completely Automated Public Turing test to tell Computers and Humans Apart. It is the process of verification to ensure that the response is only generated by humans and not by a computer or a bot. A CAPTCHA is a program that protects websites against bots. CAPTCHA is basically used in websites to prevent spam comments, spam messages, used in registration forms, contact forms etc.

How CAPTCHA works?

As I already told you, the captcha is a process to ensure that the action is done by a human being not by a bot. To ensure that an image will appear with some text on it (as you can see in below picture). You will have to type the same text in the box and submit your entry. After you submit the entry then the system will recognise whether the text submits by you and the CAPTCHA text is same or not. And this recognization is done by the means of optical character recognization (OCR). And If the CAPTCHA is matched, then it is sure that the action is performed by a human body, not by a robot application/Computer application.

what is captcha

Applications Of CAPTCHA

  • CAPTCPA is mainly used to prevent automated software from performing actions on behalf of actual humans.
  • It is used at the end of the sign-up form so as to ensure that the form is filled out only by a legitimate human and not by any of the automated software or a computer bot.
  • CAPTCHA has the ability to protect systems from malicious attacks.
  • Attackers can make use of the automated software to generate a huge quantity of requests and causing a high load on the target server. CAPTCHA’s are mainly used by websites.
  • It is used to prevent from online spam.
  • It is used to protect you from hacking process during online banking, online shopping etc. Robots may access your accounts and passwords if the captcha is not produced.
  • It help to protect website registration. For example the opening account in Yahoo, Gmail, Facebook etc. It is used to prevent robots from opening  millions of accounts in seconds. And thus captcha maintains online security.

What is reCAPTCHA?

The reCAPTCHA is developed by some students of Carnegie Mellon University. Google has acquired it in September 2009. Unlike the older CAPTCHA, you don’t have to write the text present on the image. You just need to click on a button to make sure that you are not a robot. So, it is the new way to tell that I am a human, not a bot. Now reCAPTCHA used all over the world because it saves the time of the people.

Read Also : Hindilinks4u – Watch Hindi Movies Online

Share this

Leave a Comment

For security, use of Google's reCAPTCHA service is required which is subject to the Google Privacy Policy and Terms of Use.

I agree to these terms.