What is Captcha?

What is Captcha?

Have you ever wonder what it’s Captcha, what is it for, and its trivia? Captcha, an abbreviation for “Completely Automated Public Turing test to tell Computers and Humans Apart” is a challenge-respond test in computer to determine whether the user is a human or… something else (Computer? Monkey? Alien?). It uses for protect information, such as protecting E-ticketing, web registration protection and online polls, and preventing spamming in blogs.

There are various type of captcha that you maybe ever encounter, but maybe some are not. So why don’t you check it out?

1. The standard one, distorted word captcha with a voice option

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This is the most popular captcha made by ReCAPTCHA. You need to type the obscured words above the answer section in order to process. If you can’t read the words or feel unsure what’s written, you can receive an easier distorted words by clicking “ReCAPTCHA” logo. Also, you can choose a voice option if you still cannot visualize and guess the words correctly.  

2. Picture identification captcha

This captcha was made by Picatcha, allows you to choose more than one images that match with the specific-themed question. For example, if the question is “select all the images of the Earth”, then you have to choose images that best depicts the image of Earth, usually more than one. The pictures are in basic images, so it won’t that hard to recognize the picture.

3. Math solving captcha

As you can suggest, this captcha asks you to solve a math equitation to get pass. Math solving captcha uses a very basic math, so it won’t be too hard to solved.

4. “I am not a robot” captcha

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This captcha is also one of the most common captcha in many websites. All you have to do to get pass is by simply clicking the provided box to declare yourself that you are human. This captcha is very simple and won’t wasting your time, considering many people against captcha because it is too much time consuming.

5. 3D captcha

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3D captcha might be the most difficult ones (and the most annoying ones), but will effectively kick spammers away! To get pass, you need to guess either words or image in 3D.

What do you think the hardest and the easiest captcha? Share your opinion below!

Source: 1, 2, 3, 4, 5