GnuPG uses public-key cryptography so that users may communicate securely. In a public-key system, each user has a pair of keys consisting of a private key and a public key. A user's private key is kept secret; it need never be revealed. The public key may be given to anyone with whom the user wants to communicate.

• User ID (name/email address): associate the key being created with a real person.

  (Ex: David Steele [email protected])

  • Name-Real
  • Name-Email

• Passphrase: protect the primary and subordinate private keys

• Signature

• Expire-Date

• ...

• Armor: Creating ASCII instead of binary file
• Passphrase

Data intended for some particular recipients is encrypted with the public keys of those recipients. Each recipient can decrypt the encrypted data using the corresponding private key.

• sign??
• always_trust: (true ⇒ Skip key validation)
• passphrase: use when accessing the keyrings

Note: GnuPG works on the basis of a “home directory” which is used to store public and private keyring files

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