The first thing that you need to know about unix is that it deals with
   files and these files come in many different forms. These files could
   be pieces of email which you have saved, articles which you have
   saved, or just files that you created with an editor (which is like
   creating a document with a word processor). Other files are created by
   certain programs in unix, such as elm, pine, and nn, and are used to
   configure those programs correctly. Finally, there are some files that
   are needed for your account to function and should never be removed.
   As an example, there are a couple of different ways to save a piece of
   email as a file and the method of how to do it depends on the mailer
   you are using. To find out how to do it in the various mailing
   systems, such as elm or pine or mail, refer to the related
   documentation.
   To make a file on your own, you need to use an editor. Two common
   editors are vi and pico and each of these editors have some
   documentation on them. vi is more powerful and has more documentation,
   but it is more complicated. Pico is much simpler but it is far less
   powerful and less documented. The only documentation so far is the
   link above. For beginners, pico is recommended because the added
   functionality of vi isn't needed until you become more unix
   experienced.