Digital signature is an asymmetric key cryptography where the private key is used to digitally sign a data or a message and the corresponding public key is employed to verify the signature. Furthermore, the digital signature mainly provides authentication, integrity and nonrepudiation services in a given communication, but no confidentiality service.
Much like handwritten signatures, digital signatures are cryptographic techniques that are applicable in verifying identity of entities (user, device, system, etc.). It is a piece of digital information that proves the identity of computer users.
Besides, Digital signatures functions on a pubic key cryptography scheme, which literally means entities should possess private and public keys to secure their data. A sender uses their private key to electronically sign a message. And the receiver then uses that particular sender’s public key to verify their identity and the authenticity of the message.
Digital signatures serve authentication, integrity and nonrepudiation functions, but not confidentially of data.