Asymmetric Key Algorithms

A digital signature is a hash value encrypted with the sender's private key. The receiver can decrypt the hash value with the sender's public key providing authentication, non-repudiation, and integrity. The receiver is assured that the message had indeed come from the sender. Read How digital signatures work for more information on the components involved.

Since the sender of data is provided with proof of delivery and the recipient is assured of the sender's identity, digital signatures provide non-repudiation.