199NitroPDFProfessionalsoftware user guide
Security & Digital Signatures
Using digital signatures
A digital signature is similar to an analog signature, in that it
indicates approval of the document contents at the time of signing.
The difference is that while an analog signature is represented
by a physical mark, a digital signature is represented by a set of
digital information unique to you. If a document is changed after a
signature is applied, then it is no longer the same as the document
that was approved. Hence, the signature will become invalidated.
A digital ID contains signature information that is either created by
you (known as a self-sign digital ID), or provided by a third party. A
digital ID provided by a third party will include a certificate, which
serves to confirm your signature information and help to secure your
document. When you sign a document, analog or digital, you are
indicating that you:
1. Approve the contents of the document.
2. And have the right to certify the document.
Digital IDs provided by third parties are considered more secure,
because an independent certificate authority has ratified them .
Think of it like this: a signature applied using a self-sign signature
tells a document recipient that, “This document is valid, and I am
authorized to sign this document,” while a signature applied using a
3rd party digital ID tells them that “Not only is this document valid,
but that I am authorized.”
Before you can take advantage of all the options for using digital
IDs, certifying documents, adding appearance settings, etc., you must
create at least one personal digital ID.