The vi and ex editors are the "standard" editors on Unix systems. You can count on there being some version of them, no matter what Unix flavor you are using. The two editors are in fact the same program; based on how it was invoked, the editor enters full-screen mode or line mode.
vim is a popular extended version of vi. On some Linux distributions, the vi command invokes vim in a vi-compatible mode.
This chapter presents the following topics:
Conceptual overview
Command-line syntax
Review of vi operations
Alphabetical list of keys in command mode
vi commands
vi configuration
ex basics
Alphabetical summary of ex commands
vi is pronounced "vee eye."
Besides the original Unix vi, there are a number of freely available vi clones (including vim). Both the original vi and the clones are covered in Learning the vi Editor (O'Reilly).
