CentralNotice Cyclic redundancy check From Wikipedia, the free encyclopedia Jump to: navigation , search A cyclic redundancy check ( CRC ) is an error-detecting code commonly used in digital networks and storage devices to detect accidental changes to raw data. Blocks of data entering these systems get a short check value attached, based on the remainder of a polynomial division of their contents. On retrieval the calculation is repeated, and corrective action can be taken against presumed data corruption if the check values do not match. CRCs are so called because the check (data verification) value is a redundancy (it expands the message without adding information ) and the algorithm is based on cyclic codes . CRCs are popular because they are simple to implement in binary hardware , easy to analyze mathematically, and particularly good at detecting common errors caus...