OpenPGP is a PKI standard that uses the web of trust to validate the public key.
It's defined by RFC4880 (OpenPGP Message Format) that define how to securely provide:
in order to protect its privacy.
In general, the terms GnuPG, GPG, GNU Privacy Guard, OpenPGP and PGP are used interchangeably.
To not get confuse, OpenPGP is the standard/reference and the following software implements it:
PGP, Pretty Good, and Pretty Good Privacy are trademarks of PGP Corporation and are used with permission.
See the terms section.
Steps: