The vi Editor vi is a pure example of the Unix philosophy of using a single small program to accomplish a specific task. It is the traditional editor that is still found on nearly every Unix workstation, and despite its non-intuitive command set, it is quite powerful once you learn how to use it. Various vi clones abound, such as elvis , vim , and vile , but a rose by any other name is still a rose. Hit the ESC key to return to edit mode. The edit mode is made for speed.
Most commands are one or two keystrokes.
You won't find multi-column displays or tables in this little editor, but vi was built to be extensible . You can easily issue shell commands or call macros from vi 's command line. Unix is full of small programs that do a single task that can be called from another program that does a single task. One of the biggest strengths of vi is that it doesn't require many system resources at all. So if you fry your system and you're only able to get a crippled system to boot, vi will still run just fine.