Why on earth would I want to use a text based editor, when I have nice GUI mouse oriented editors on my PC? The answer is Emacs runs on your Unix platform, so you can make minor changes easily. Basically you have 2 choices for maintaining your works in progress on a Unix platform over the internet.
1. Create the file using a fun, graphic, mouse friendly text editor on your PC. Then FTP the file to your Unix server. When you make a change, save your changes and FTP it again. This method has the advantage of allowing you to do all your work in a comfortable, mouse oriented editor. The disadvantage is the amount of time spent uploading the file with every minor change.
2. Learn a Unix editor, such as Emacs, and save your changes right to the server. It's not pretty, and you can't use a mouse, but it can do everything you want it to do once you get used to it. I would much rather use Emacs to make a minor adjustment than upload my changes every time.
NOTE: I actually use an editor called Pico. Like Emacs, it runs on the Unix platform, so I can make changes directly on my server. It is a little bit easier to use and the command menu is always at the bottom of the screen. Type pico filename to open a file with Pico.
To launch the Emacs tutorial:
Type emacs and press [ENTER].
Type [ctrl]-h and then press t.
Save a file by typing [ctrl]-x and then [ctrl]-s.
Type emacs filename to open a file with Emacs.
You're ready to start working with Perl.