Must have upper and lower case letters, numbers, not less than eight and not more than twenty.

Password is a technique used for obfuscation, where the user wishes to transform normal (recognizable) information into unrecognizable information. However, this unrecognizable information can be partially reprocessed and recovered and cracked. Password in Chinese is a generic term for "password". The "password" you enter when logging into a website, e-mail address, or withdrawing money from a bank should strictly speaking only be called a "password" because it is not an "encryption code" in the original sense of the word, but it can also be called a secret number. But it can also be called a secret number. It is a system of symbols that is primarily limited to individual understanding (e.g., a message). Such as ciphered telegrams, ciphered typewriters.