1. The MD5 calculation, The entire file or character string is calculated through its irreversible character string transformation to generate the MD5 hash value of the file or character string. Any two files and strings will not have the same hash value (that is, "very likely" is different, in theory, it is difficult to create two strings with the same hash value).
2. MD5 is often used to verify character strings or files to prevent files and character strings from being "tampered". If the MD5 hash value of the file and the string is different, the content of the file is also different, that is, modified. If you find that the downloaded file is different from the MD5 value, you need to use it carefully.
3. MD5 file verification has many uses, such as: game patch package verification, virus file verification, APP review verification, etc .; if you want to confirm the integrity and correctness of a certain file, MD5 will be used for verification.