what is captcha code

CAPTCHA stands for "Completely Automated Public Turing test to tell Computers and Humans Apart". It is a type of security measure known as challenge-response authentication that helps protect websites and online accounts from spam, promotion spam, registration spam, and data scraping by asking users to complete a simple test that proves they are human and not a computer trying to break into a password-protected account. CAPTCHA tests are made up of two simple parts: a randomly generated sequence of letters and/or numbers that appear as a distorted image, and a text box. To pass the test and prove human identity, users simply type the characters they see in the image into the text box. CAPTCHAs are designed so that humans can complete them, while most robots cannot. There are different types of CAPTCHAs, including text-based CAPTCHAs and image-based CAPTCHAs.