Let's get acquainted with CAPTCHA and its types!

What is CAPTCHA? So, CAPTCHA stands for Completely Automated Public Turing test to tell Computers and Humans Apart. CAPTCHA is a tool that can distinguish between real users and robots or machines, such as bots. CAPTCHAs provide challenges that are difficult for computers to solve but relatively easy for humans.

Since the introduction of CAPTCHA, bots that use machine learning have also evolved. Bots are better able to identify traditional CAPTCHAs with algorithms trained in pattern recognition. Therefore, a new CAPTCHA method was created based on more complex tests. For example, Google's reCAPTCHA requires the user to click in a certain area and wait for the time to run out.

Types of CAPTCHAs

Text-based CAPTCHA
Text-based CAPTCHA is the simplest way in which this CAPTCHA can use a known word or phrase, or a random combination of numbers and letters. Some text-based CAPTCHAs also include capitalization variations.

Picture Recognition CAPTCHA/ Image CAPTCHA
These CAPTCHAs use recognizable graphic elements, such as photos of animals, shapes, or landscapes. Typically, image-based CAPTCHAs require the user to select an image that matches the theme or identify an image that does not.

Math CAPTCHA
This CAPTCHA prompts the user to solve a simple math problem such as "4+1" or "18-3". Although simple, it turns out that this CAPTCHA can be difficult for robots to solve and compose answers, thus making this type of CAPTCHA classified as safe.

I'm not a robot CAPTCHA
This type of CAPTCHA is created by Google. This CAPTCHA is quite easy because the user only needs to tick "I'm not a robot" in the checkbox to determine if the user is a human. This CAPTCHA tracks movement, and if the checkbox is checked directly in the middle, it's a robot. Why? Because the robot is very methodical, so it is easy to determine based on its behavior. Humans will most likely not click directly in the middle but in some other area of ​​the box.

Of the several examples of CAPTCHAs above, which one do you encounter the most. Do you think that CAPTCHAs make accessing difficult for you?