ReCAPTCHA
ReCAPTCHA is a common method of protecting websites from spam bot activity.
This is a free identity verification system that protects the site from various forms of .
How does reCAPTCHA work?
ReCAPTCHA is a Google product and 3 versions of this service have been released so far. The first stopped working in 2018. The other two are still in use and being improved.
ReCAPTCHA v2
The reCAPTCHA v2 widget provides image recognition tests. Users must identify images that contain certain objects, such as animals, trees, street signs or bridges. It is often necessary to isolate objects from blurry images, but this is possible because people are used to perceiving objects in different contexts and situations.
As millions of users identify garbled text and select objects in blurry images, the data is fed into AI systems to advance machine learning. ReCAPTCHA uses image annotation solutions and datasets to train intelligent machines.
ReCAPTCHA v3
reCAPTCHA v3 uses an advanced risk analysis algorithm that takes into account the time it takes to enter data into the forms. To prevent it from being hacked, Google doesn't reveal any details about how the algorithm works. It is recommended to use the reCAPTCHA v3 service on multiple pages, not just for registration or login. Specific user interactions with a website can be used to better judge whether actions are human or bot actions.
