VIM - Vi iMproved
Revised: October 2003.
vim is a "vi workalike". That is, when run by itself it's almost functionally identical to vi. However, vim has many added features above and beyond what vi has to offer.
If you are new to both vim and vi, then your best bet would be to learn vi first. It is faster (and less CPU intensive) to run vi because vim is bloated with extra features. Once you have mastered the basics of vi, then you can move on to the extra features of vim.
For a beginners guide to vi, see the online vi tutorial.
Your vim configuration is highly customizable. To avoid needing to re-enter your vim preferences every time you start the program, you can save commands in a .vimrc file in your homedirectory. This file is read every time you run vim.
Sample vimrc files can also be downloaded from the vim web pages at http://www.vim.org.
One of the more popular features of vim is syntax highlighting. This will colorize keywords and patterns in variety of files. For example, with syntax highlighting on, a C++ file will have all the keywords in one color and curly braces in another color.
To turn on this feature, type ":syn on" in vim or add "syn on" to your .vimrc file. Keep in mind, however, that you will need a color enabled terminal to see the effects. Normal xterms cannot view ansi color. On the Sun workstations you can use /usr/dt/bin/dtterm .
The official vim homepage http://www.vim.org contains a great deal of additional documentation (and links to still more documentation).
You can also purchase a copy of The Vim book by Steve Oualline, and simultaneously help orphans in Uganda athttp://iccf-holland.org/click5.html. (Not a joke - check it out.)