Captchas

Everyone on the internet is aware that robots are unable to recognize traffic signals among a set of nine squares. The last line of protection against robot invasion on a website is the captcha test, which uses multiple layers of information, including your IP address, browsers, plugins, keystrokes, and more, to confirm that you are a human and not a robot.

The reason these tests are growing harder—and sometimes even tricking you on the ones where you have to recognize text that seems garbled—is that robots are actually getting better at them, making them more difficult to pass. In several tests, robots are already far superior to humans. However, we're still ahead of the curve for fundamental programming, so it will have to do until we come up with something better, like the various game-like exams or ink blot puzzles that have been attempted.

It has the ability to read captcha images, such as the one in your figure. One of the most recent algorithms that employs neural networks to learn text data is this one. There are various different algorithms that are able to recognize it. This is the precise reason Facebook and Google switched to an image-based recognition captcha.