A digital signature is a cryptographic technique used to verify the authenticity and integrity of digital messages, documents, or transactions. It provides a way to confirm that a message or document was indeed created by a particular sender and that it has not been altered or tampered with during transmission. Owner used to create the digital signature, while the public key is freely available and is used to verify the signature. Digital Signature Certificate contains your name, a serial number, expiration dates and the DSC-issuing by authority (CA) so that a recipient can verify that the certificate is real & verify that whose signature is attached to the document and that the message has not been altered either intentionally or accidentally from the time it was signed. Also the signer of a document cannot latter disown it by claiming that the signature was forged.