What is CAPTCHA?

What is CAPTCHA?

The 'Completely Automated Public Turing test to tell Computers and Humans Apart', or CAPTCHA for short, is a website security tool which is used to separate, or define, the difference between real users and automated users, such as bots. CAPTCHA's produce challenges that are difficult for computers to perform but relatively easy for human users.

How CAPTCHA Works?

CAPTCHA's operate by providing information or a challenge to a user for them to complete. Traditional CAPTCHA tools provide a string of letters or numbers which a user needs to match and submit, before they can complete or confirm an action on a website or app.

However, since CAPTCHA tools have been introduced and used, machine learning tools have been developed with increasing accuracy to identify characters and patterns which have allowed bots and tools to pass any CAPTCHA challenges. To protect against this, newer and more complex CAPTCHA methods and challenges have been developed.

How Is CAPTCHA Used?

CAPTCHA tools are normally used within a website or app to restrict access, or the completion of forms by non-human users, bots and automated tools.

Prevent False Comments

CAPTCHA tools can prevent automated tools or bots from spamming comment areas, contact forms, review or message sites.

This can improve the overall quality and level of information within a site and reduce the number of resources which a website or app is using.

Online Polls

Using CAPTCHA tools within a poll can ensure that they are completed by human users so that the results are not skewed.

Where a CAPTCHA tool will be unable to limit the number of entries within a poll, to discourage multiple votes from single users, a time limit can be introduced instead. For example, 1 vote from a user every 5 hours.

Preventing Price & Quantity Manipulation

As well as being able to prevent the false or multiple registrations for free events, CAPTCHA can be used to limit the number of purchases which are made by a single user.

This is helpful in the case of event ticket purchases to restrict scalpers from purchasing a large quantity of event tickets for resale.

Registration Limits

Online services which allow for the free registration to access products and services within an account, can use CAPTCHA tools to prevent automated systems or bots from creating fake accounts.

In Summary

CAPTCHA, which is an abbreviation of 'Completely Automated Public Turing test to tell Computers and Humans Apart', is a security test used by websites to check if a user is a real human, or an automated computer program.

Related Information

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Further Information, Websites & Links

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