What Is a CAPTCHA?

Many people have seen them and used them, but they don't understand what a CAPTCHA is. What is a CAPTCHA anyway?

First of all, CAPTCHA is not a word. Instead, it is an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart."

It is a program that protects websites by generating tests that only humans can pass. CAPTCHAs prevent automatic form submissions. For example, only humans and not computers can read distorted text or numbers.

Visual CAPTCHA

CAPTCHAs prevent automatic form submissions. For example, only humans and not computers can read distorted text or numbers that users are asked to type to prove it is human activity. The letters or digits come from a distorted image that appears on the screen that only humans can understand.

If at first, the CAPTCHA is not successful, a person can try another image until he is successful.

CAPTCHAs are not limited to letters and numbers. CAPTCHAs may also include other tests. One might have to identify an object that does not belong in a particular set of objects, locate the center of a distorted image, or identify distorted shapes.

CAPTCHA
CAPTCHA | Source

Audio CAPTCHA

While the first choice for a CAPTCHA is visual, there is another way to prove someone is a human. If a person cannot see the CAPTCHA, he can use the audio device that has been provided.

Audio Captcha
Audio Captcha | Source

CAPTCHAs Are Useful

CAPTCHAs weren't designed to make people's lives miserable. They are useful. The test is supposed to be simple, but sometimes they are difficult to read. Sometimes it takes at least three tries to prove that a person is human. Then the audio is difficult to hear and understand. Often this getting the CAPTCHA is time consuming.

Are you familiar with CAPTCHAs?

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Which CAPTCHA do you prefer?

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Comments 6 comments

revmjm profile image

revmjm 5 years ago from Richmond, VA Author

I don't think CAPTCHAs were designed to make my life miserable. I know they are useful, but I still think they are annoying and inconvenient.


DOGS 101 profile image

DOGS 101 5 years ago from Planet Earth

What Is A CAPTCHA Anyway? Should I bark or wag my tail? Is it something for a dog to eat or drink? What Is A CAPTCHA Anyway?


revmjm profile image

revmjm 5 years ago from Richmond, VA Author

Dogs 101: thanks for reading and responding. However, a CAPTCHA has nothing to do with dogs. CAPTCHA is used on computers. CAPTCHA is an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart."


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Miss Capri 5 years ago

Yes! *Grins* I detest captchas too, because they are inexcessible for the most part, and sometimes don't even work if you put in the correct answer because the script/code is buggy. They forgot about the visually impaired and the deaf when they came up with captcha, even the audio ones block out the deaf-blind. Some sites thankfully use truly accessible captchas now, in the form of a simpl question in text format that you type the answer to, and all good captchas should never require you to see an image or hear a sound to prove you are a human.


revmjm profile image

revmjm 5 years ago from Richmond, VA Author

Miss Capri, thanks a lot for reading and responding to this article about captchas. You seem to know exactly what I mean.


revmjm profile image

revmjm 5 years ago from Richmond, VA Author

Thanks, captchamonster, for your comment about CAPTCHA tests.

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