Term of the Moment
Ken Thompson Hack
Definition: hash function
An algorithm that turns a variable amount of data into a small, fixed-length value called a "hash value," "hash code," "digest" or "digital fingerprint." See SHA, hash, Merkle tree and cryptographic hash function.
The Hash Is Always Fixed in Length
No matter the size of the message (the data being hashed), the resulting hash is a fixed length binary number that cannot be converted back into the original data. For example, the SHA-256 hash algorithm generates a 256-bit result no matter the size of the original input. The hash serves as a digital fingerprint of the original data.