Definicja digital signature (BC-SEC)

A security mechanism for protecting digital data.

The digital signature serves the same function for the processing of digital data as a handwritten signature serves for paper documents. Its purpose is to guarantee that the individual (or component) that signs a digital document really is who he or she claims to be. It also protects the integrity of signed data; if even one bit in either the signed data or in the signature is changed, then the signature is invalid.