GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP). GnuPG allows to encrypt and sign your data and communication, features a versatile key management system as well as access modules for all kinds of public key directories. GnuPG, also known as GPG, is a command line tool with features for easy integration with other applications. A wealth of frontend applications and libraries are available. Version 2 of GnuPG also provides support for S/MIME and Secure Shell (SSH).

Summary:

• A short installation guide
• Invoking GPG-AGENT
• Invoking GPG
• Invoking GPGSM
• Invoking the SCDAEMON
• How to Specify a User Id
• Helper Tools
• How to do certain things
• Notes pertaining to certain OSes
• How to solve problems