Basic VI commands

The most commonly used commands in vi Editor are as follows:

COMMAND	DESCRIPTION
a	starts insert mode after current position of cursor.
A	starts insert mode at end of the current line.
cw	Deletes the current word and than enters the insert mode to replace that word.
dw	Deletes the current word without entering the insert mode.
dd	Deletes the current line.
G	Moves cursor at the end of the line.
15G	Moves cursor to fifteenth line.
h	Moves cursor left one space.
I	Enters insert mode.
o	enters insert mode opening line below current cursor.
O	enters insert mode opening line above current cursor.
:q	Exits from vi.
r	Replace; replaces current character with next character.
:set nu	shows line number for the current line
u	Undoes the last change
:w	Writes the current file.
Esc	Escapes from insert mode
/system	Searches the word System in current file