In short, an electronic signature is a signature on an electronic document.

An electronic signature is defined as "contained in a data message in electronic form with data for identifying the identity of the signer and indicating the signer's approval of its contents." The traditional paper signature or seal function is realized by technical means to confirm the true identity of both parties to the transaction and ensure the security, authenticity and non-repudiation of the transaction. "

Signing an electronic signature on an electronic file is to encrypt the electronic file and its message digest data with a private key. There are many ways, such as automatic signature, click signature, SMS signature, video signature and so on.