checksum

n. a unique alphanumeric value that represents the bitstream of an individual computer file or set of files

Notes

The term checksum is often used interchangeably with other types of fixity tools such as cryptographic hash values generated by algorithms such as MD5, SHA-1, and SHA-256. Checksums or hashes are used in the context of digital preservation, such as during the process of transferring or storing files, in order to determine whether files have been inadvertently altered. For example, an archivist can compare checksums or hashes generated before and after file transfer to determine whether the file has maintained the same value through the transfer process.