How to view your mobile phone verification code?

Press *#06# on your mobile phone and an IMEI code will appear. The first 6 digits (TAC) are "model approval numbers", which generally represent models. The next two digits (FAC) are the "last assembly number", which generally represents the place of origin. The 6-digit number (SNR) is followed by the "serial number", which generally represents the production serial number. Finally, 1 bit (SP) is usually "0", which is a check code and is reserved for the time being.

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1, CAPTCHA is the abbreviation of "automatic public Turing test tells computer and human part", and it is a public * * * automatic program to distinguish computer from 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 by using a specific program brute force cracking method.

2. In fact, using verification code is a popular way for many websites now, and we have also 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.