What is a hash algorithm?
An algorithm that transforms a string of characters into a usually shorter value of a fixed length or a key that represents the original value. This is called the hash value. Hash functions are employed in symmetric and asymmetric encryption systems and are used to calculate a fingerprint/imprint of a message or document. When hashing a message, the message is converted into a short bit string – a hash value – and it impossible to re-establish the original message from the hash value. A hash value is unique in the sense that two messages cannot result in the same bit string, and any attempt to make changes to the message will negate the value and thus the signature.
