A digital signature is an electronic form of a signature that is used to authenticate the identity of the sender of a document, as well as to ensure that the original content of the document that has been sent remains intact. It uses encryption technology and public key infrastructure (PKI) to create a secure, legally binding agreement between two parties. Just like a handwritten signature, it adheres the signatory to the document, creating a secure record and proof of authentication. Digital signatures are increasingly being used in business as they provide an additional layer of trust and security for sensitive documents.