I have set up this page in response to questions I get about PGP -
what it is, where to get it, and how to use it.
PGP (short for Pretty Good Privacy), created by Philip Zimmermann,
is the de facto standard program for secure e-mail and file encryption
on the Internet. Its public-key cryptography system enables people who
have never met to secure transmitted messages against unauthorized
reading and to add digital signatures to messages to guarantee their
Why do we need PGP? E-mail sent over the Internet is more like paper
mail on a postcard than mail in a sealed envelope. It can easily be
read, or even altered, by anyone with privileged access to any of the
computers along the route followed by the mail. Hackers can read
and/or forge e-mail. Government agencies eavesdrop on private
For further discussion of what PGP is for, and what it can do, read
the following articles:
More detailed information about PGP, and copies of the program itself
for various platforms, can be found from the links given below.
Basic tutorials for beginners
There is considerable overlap between these tutorials. If you don't
find the information you need in one of them, try another, or try the
FAQ. Some of these sites are
out of date, referring only to older versions of PGP, but they still
provide generally useful information.
for RISC OS. Here you can find a collection of PGP software and other
security utilities for RISC OS (Acorn) computers. There is also a
RISC OS version of GnuPG, which is compatible with (and even superior to)
modern versions of PGP.
Various versions up to PGP are available for many different operating
systems, but not every version exists for every platform. Whichever
operating system you use, you can find an appropriate version on one of the
"Ius mentis" - General information about PGP and other security tips.
The UKERNA Secure E-Mail Project
The United Kingdom Education and Research Networking Association
(UKERNA) runs the Joint Academic Network (JANET) on behalf
of the Academic Community of the U.K. (approximately ac.uk). UKERNA
sees the current solution to authentication and privacy of documents to be PGP
and is investigating how PGP can be made easy to use for sending e-mail.
How PGP works (in part)
If you are mathematically inclined and understand (or are willing to learn)
a little about modular arithmetic, you can read about the maths behind
some public-key cryptosystems at the following URLs: