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Introduction about CAPTCHA.

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What is CAPTCHA?

A CAPTCHA acronym - Completely Automated Public Turing test to tell Computers and Humans Apart

CAPTCHA is a type of challenge-response test used in computing to determine whether or not the user is human.

A CAPTCHA differentiates between human and bot by setting some task that is easy for most humans to perform but is more difficult and time-consuming for current bots to complete.

CAPTCHAs are often used to stop bots and other automated programs.

Sample Example for CAPTCHA
image

Advantages:

1)Distinguishes between a human and a machine
2)Makes online polls more legitimate
3)Reduces spam and viruses
4)Makes online shopping safer
5)Diminishes abuse of free email account services

Disadvantages:

1)Sometimes very difficult to read
2)Are not compatible with users with disablilities
3)Time-consuming to decipher
4)Technical difficulties with certain internet browsers
5)May greatly enhance Artificial Intelligence

Video for What is Captcha

References

http://searchsecurity.techtarget.com/definition/CAPTCHA
http://d585tldpucybw.cloudfront.net/sfimages/default-source/productsimages/asp.net-ajax/productitemfeatures/captcha_various-protection-modes-_screenshot-gif.gif?sfvrsn=0
http://www.ewebdiscussion.com/web-and-graphics-design/1834-advantages-and-disadvantages-of-using-captcha.html
posted Nov 27, 2014 by Ujjwal Mehra

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CAPTCHA is like artificial intelligence service provided for the online security purpose.
Captcha code is available in both numerical and alphabetic way. If any user accesses some site and edits some information in the websites, captcha code is used for the security  purpose so that customer can easily access the websites. While the captcha code is not matched the required code than the customer can't able to access the website.
commented Aug 4, 2016 by Magento_ocodewire


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