Cryptography
hashing
integrity
security
What is Checksum?
Definition
A checksum is a small value derived from a data block, used to detect errors or verify integrity. Common checksum algorithms include CRC32, MD5, and SHA-256. If the data changes, the checksum changes.
Why It Matters
Checksums verify that files were not corrupted during download or transfer. Package managers (npm, pip), ISO images, and software releases publish checksums so users can verify authenticity. They are also used in networking protocols to detect transmission errors.