A digital signature is an electronic form of a signature that can be used to authenticate the identity of the sender of a digital message or document. It is used to verify that the sender is who they claim to be and that the message or document has not been altered in transit.
Digital signatures use cryptographic algorithms and public key infrastructure (PKI) to create a secure signature that can be verified by anyone with access to the public key. The signature is created by the sender using their private key, which is known only to them. When the signature is verified, the recipient can be sure that the sender is who they claim to be and that the message or document has not been altered in transit.
For example, when a person sends an email, they can digitally sign it with their private key. The recipient can then use the sender’s public key to verify the digital signature and ensure that the message has not been tampered with.