When using Emacs to handle your mail, your letters get copied from the Unix mail spool to an RMAIL file. While you can edit RMAIL like any other file, it is written in a special format designed for using Emacs in the mail mode. Letters are easier to read and write than with the ordinary mail command, and if you usually use Emacs for your editing, you should find the Emacs mail system a natural. To use Emacs for your mail you must first invoke Emacs (or have it already running for regular editing purposes). You then switch Emacs to a ``read mail'' or ``send mail'' mode and buffer and use the regular Emacs commands with the supplements: