Significance of CRC while comparing class files

Question

What does CRC mean while comparing two files?

Answer 1

This is exactly from the Beyond Compare's website:

A CRC is a 4-byte mathematical checksum of a file's contents. If a pair of files have different CRCs, then you can be sure their contents are different. If they have matching CRCs, then it's likely (but not certain) that their contents match.