From MEPIS Documentation Wiki
Vi or Vim is a basic text editor found in most of UNIX-like operating systems. It is useful to know how to use it in case there are no other text editors available, it is also a very powerful editor.
Vim is "vi improved" and it usually replaces "Vi" on most of the modern systems.
Start Vim tutorial by typing "vimtutor" in konsole. If that doesn't work make sure you have "vim-full" installed on your system.
Vi has two basic modes "command mode" and "insert mode", you can enter text only in insert mode, otherwise Vim expects a command. Vim starts in command mode, to enter insert mode press "i", to exit back to command mode press "Esc".
exit to command mode Esc
exit vi (without saving) :q!
exit vi (with saving) :wq
All these commands place you in "edit mode" to exit press Esc.
insert mode i
append mode A
open new line o
copy (or yank) y
copy word yw
delete character x
delete word dw
delete line dd
delete 5 lines d5d or 5dd -- many commands in Vim can be applied multiple times by using a number with them, for example d3w deletes three words and 7x deletes seven characters.
put or paste p pastes the deleted content
undo all changed to a line U
Search and replace
search backward ?
search again (next) n in opposite direction N
replace in all the line :s/old/new/g
replace in all document :%s/old/new/g
go to original position CTRL-o
go to line number linenumber G, or linenumber gg
go to begin of document gg
go to end of document G
show position in document CTRL-g
start program with vi filename
in vi type :o filename
save as :w filename
Other useful commands
execute external commands :!command, for example :!ls runs the "ls" command in the current directory.