It lets you communicate securely with people you've never met, with no secure channels needed for prior exchange of keys. It's well featured and fast, with sophisticated key management, digital signatures, data compression, and good ergonomic design. If you really want to learn how to use it properly, it's best to read the full documentation that comes with the system, which is very complete. It's important that this be kept secret.
Options take string, numeric, or boolean values.
Keywords can be abbreviated to unique prefixes. Keywords are not case-sensitive. The user may also override this setting by specifying a user ID on the PGP command line with the -u option. Canonical text has a carriage return and a linefeed at the end of each line of text. This mode is automatically turned off if PGP detects that the plaintext file contains 8-bit binary data.