Authentication, like authentication in reality, needs to verify the user's identity by some means. Authentication is a way to gain trust in someone or something.

Digital signature is an encrypted message digest, which is used to confirm the identity of the sender and the integrity of the message. Digital signature is similar to handwritten signature, except that digital signature is analog and varies from person to person. A digital signature is a numeric string consisting of 0 and 1, which varies from message to message. Digital signatures meet the following requirements:

The receiver can confirm the sender's signature, but can't forge it.

After the signature is issued by the receiver, it cannot be denied.

The receiver cannot deny the received signature message, that is, it has the authentication of receiving the message;

A third party can confirm the message transmission between the sender and the receiver, but it cannot forge this process.