GNU Privacy Guard
GNU Privacy Guard (GnuPG or GPG) is a free-software replacement for Symantec's cryptographic software suite PGP. The software is compliant with the now obsoleted RFC 4880, the IETF standards-track specification of OpenPGP. Modern versions of PGP are interoperable with GnuPG and other OpenPGP v4-compliant systems. November 2023 saw two drafts aiming to update the 2007 OpenPGP v4 specification (RFC4880), ultimately resulting in the RFC 9580 standard in July 2024.