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 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.
gpg4win provides a windows version of gnupg.
gpgtools provides a mac os x version of gnupg.
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