There are differences between electronic signatures, which people often do not even realize. An electronic signature is not a secure signature, by itself. The signature, along with the document it is attached to, can be altered, forged and modified. In order to prevent this, the signature must be encrypted using a digital certificate. Secure electronic signatures which have been encrypted with a digital certificate are called a digital signature.
A Digital Signature Is Part of a Digital Certificate Which Must Be Added
In order to use a digital signature, you will need to have it added to the contents of a digital certificate. This process will involve using a certificate authority system to generate these certificates. For each certificate generated, there will be a second certificate also generated. One certificate will contain a private key, which encrypts the signature. The other certificate will contain a public key, which decrypts the signature.