Cyclic Redundancy Check. The CRC checksum is a 32-bit checksum that is often used to verify the integrity of data. While slightly more reliable than an Adler-32 checksum, the CRC checksum takes longer to compute. 

When uncompressing data that contains an embedded checksum, the checksum can be used to ensure that the resulting uncompressed data is very probably identical to the original data, because 32-bit CRC checksums are able to detect single bit variations even in the largest files. 

The 32-bit CRC checksum is a popular checksum that is used by the Zip archive file format and the Zmodem communications protocol, for example.