Error detection and correction (EDAC) are techniques used to detect and correct errors that may occur during the transmission or storage of digital data.

Error detection involves adding extra information, called a checksum, to the data being transmitted or stored. The receiver or storage system can use this checksum to verify that the data has been received or stored correctly. If the checksum does not match the data, it indicates that an error has occurred and the data must be retransmitted or corrected.