VI is a text editor that should not be used unless there is no other option available. VI has a huge learning curve for and minimal amount of functionality.
VI has two modes; insertion and command.
Command Mode:
:x Exit save changes
:q Exit if there are no changes
:q! Exit ignore changes
ZZ Exit and save changes
Insertion Mode:
i Insert before cursor
I Insert before line
a Append after cursor
A Append after line
Links to VI information:
http://www.tuxfiles.org/linuxhelp/vimcheat.html
http://www.eec.com/business/vi.html
http://www.eng.hawaii.edu/Tutor/vi.html
