The command gpg is part of GnuPG. GnuPG stands for GNU Privacy Guard and is GNU's tool for secure communication and data storage. It can be used to encrypt data and to create digital signatures. It also includes an advanced key management facility. GnuPG works on Linux and UNIX like operating systems as well as for Windows and Mac OS¬†X.
Article Source Linux Journal
August 20, 2009, 9:25 am¬†