A Simple File Verification file is used to verify data. A CRC32 checksum value is stored in a file that typically, but not always, has the .SFV file extension.
Checking and Creating SFV Files
A program that can calculate the checksum of a file, directory, or disk is used to produce the SFV file. The purpose is to verify that a particular piece of data is actually the data you expect.
The checksum changes with each character added to or removed from a file, and the same goes for files and filenames in directories or disks. This means that the checksum is unique for each piece of data, even if one character is off, the size is slightly off, etc.
For example, when you check the files on a disc after burning it from a computer, the program performing the check can verify that all the files that were supposed to be copied are actually on the CD.
