CRC Values

CRC values are calculated using an algorithm known as the Cyclic Redundancy Check, or "CRC" for short. Basically, this involves generating a 32-bit number (or "CRC value") based on the contents of a file. If the contents of a file change, its CRC value changes as well. This allows the CRC number to be used as a "checksum" in order to identify whether or not the file has changed. It also allows you to distinguish between different versions of a file by comparing its CRC value to the CRC values of the originals.

A file doesn't have to change much for its CRC value to be different. In fact, if even just one bit in a file changes, the CRC value for that file will change as well. If all you did was change one letter in a readme.txt file between version 1 and version 2, the CRC value for that readme.txt file would be completely different.

CRC values can be calculated for any type of file.

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