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What is Completely Automated Public Turing Test to Tell Computers and Humans Apart (CAPTCHA)?

As technology has advanced, cybercriminals have relied more on bots to assist in network compromise. Bots are software applications designed to execute various internet tasks at a much higher rate than humans. For this reason, many companies have implemented tools to differentiate between real users and bots called CAPTCHAs. CAPTCHA stands for Completely Automated Public Turing Test to Tell Computers and Humans Apart. CAPTCHAs create tasks that must be completed by a human user. The tasks are specifically designed to be nearly impossible for bots to complete.

CAPTCHAs are used by various websites to eliminate bot activity. They are often set up to guard the integrity of websites that allow users to create a personal account. Hackers utilize bots to create fake accounts that collect valuable data.

Types of CAPTCHAs

Text-based CAPTCHAs - These CAPTCHAs were the first method in which websites were able to verify the humanity of users. Text-based CAPTCHAs use commonly-used words or phrases with variations of capitalizations and numbers. They are often delivered in diverse patterns, making it more difficult for bots to recognize the needed algorithms.

CAPTCHA Images - As CAPTCHAs have become more prevalent, images have become a useful tool to verify users. Image-based CAPTCHAs require users to select a particular theme from an assortment of images. Themes vary from each CAPTCHA and can include requests such as, “Select all images below that contain a bus.” Image-based CAPTCHAs are more complex than text-based CAPTCHAs, making it more difficult for bots to navigate through the security gate. In most cases, bots are unable to use image recognition or semantic classification.

Audio CAPTCHAs - The downfall of Image-based CAPTCHAs is that visually impaired users are unable to verify their humanity. For this reason, audio-based CAPTCHAs were developed. This nxtsoft.com/security page 2 © 2021 NXTsoft verification process provides users with a series of audio clips with a series of numbers and letters. Users then enter what they hear to gain verification. The audio clips make it difficult for bots to separate characters from other sounds.

Basic Math CAPTCHAs - Basic equations and word problems are also used to deter bots. Most bots are unable to recognize what is being asked leading to an incorrect response. Math problems are rarely anything other than basic addition or subtraction problems.

Alternative Sign In through Social Media - Many websites have started to use the popular method requiring sign in through a separate account already created on social media. This is a popular option for both the website and the user. For the user, this method allows them to avoid the many steps of creating a new account as most of their information is transferred from the established account. For the website, the method provides faster verification based on the completed verification of the social media platform.

Summary:

Bots are software applications designed to execute various internet tasks at a much higher rate than humans. For this reason, many companies have implemented tools to differentiate between real users and bots called CAPTCHAs. CAPTCHA stands for Completely Automated Public Turing Test to Tell Computers and Humans Apart. CAPTCHAs are used by various websites to eliminate bot activity. They are often set up to guard the integrity of websites that allow users to create a personal account. There are multiple types of CAPTCHAs including text, image, audio, math, and social media sign in.

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