Why do you always receive text messages from Tencent WeChat verification code?

It's because someone else entered your mobile phone number when logging in to WeChat. Be careful, you need to change your password to avoid being stolen by others.

CAPTCHA is the abbreviation of "automatic public Turing test to distinguish between computer and human", and it is a public * * * automatic program used to distinguish whether the user is a computer or a human.

It can prevent malicious password cracking, ticket brushing and forum flooding, and effectively prevent a hacker from constantly trying to log in to a specific registered user and using a specific program to violently crack. In fact, using verification code is a popular way for many websites now, and we have realized this function in a relatively simple way.

This question can be generated and judged by computers, but only humans can answer it. Because the computer can't answer CAPTCHA's question, the user who answers the question can be considered as human.

The verification code of most websites needs to click the fill-in box, and then the verification code picture will automatically pop up. Because the verification code is randomly generated, there is a great chance that there will be a picture of the verification code that cannot be clearly identified, so it should be noted that the general website will have corresponding prompts, such as "I can't see it clearly, change it". If there is no prompt, click the current verification code picture directly to complete the replacement of verification code.