CAPTCHA is "Completely Automated Public Turing test to tell Computers and Humans Apart" The abbreviation of "Fully Automated Turing Test to Tell Computers and Humans" is a public, fully automated program that distinguishes whether a user is a computer or a human.
Function of verification code:1. Prevent ticket brushing, forum flooding, and page brushing
2. Prevent hackers from maliciously cracking passwords and stealing user data
Verification codes usually use some lines and some irregular characters. The main function is to prevent some hackers from Password digitization theft.
Effectively prevents a hacker from constantly trying to log in to a specific registered user using a specific program to brute force. In fact, using verification codes is a common method on many websites now (such as China Merchants Bank’s online personal banking, Baidu Community), we implemented this function in a relatively simple way. Although logging in is a little more troublesome, this function is still necessary and important for the password security of netizens.2. Prevent malicious registration and login
Verification codes are generally used to prevent batch registration, which is difficult for the human eye, let alone a machine. Almost all formal forums require you to enter a verification code when registering. This is to prevent people who spam advertisements from using registration machines to register maliciously.
Type of verification code● Gif animated verification code
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