Vi For Smarties

Colon Commands (Ed/Ex Commands)

Use : (colon) in command mode before entering complex commands.
Example: :%s/foo/bar/g replaces all occurrences of foo with bar in the entire file.
Example: :set nu displays line numbers.
Example: :set nonu cancels line number display.
Example: :1,8d deletes lines 1 through 8 inclusive.

Use :set wm=8 to make text wrap around to a new line if it goes beyond column 72 of the current line. (80-8=72) The 8 can be some other value if you wish, of course.
Use :set ts=4 to set the number of spaces used to display the tab character to 4. The 4 can be some other value if you wish.
Use :set ic to make string searches with / ignore cases.
Example: After :set ic using /foobar will find foobar as well as FooBaR.

Use ma to mark the current line as a. The a can be any letter from a to z. The line can then be referenced by using 'a (single quote followed by a or appropriate letter).
Example: 'a goes to the line marked as a.
Marked lines can be used in colon commands.
Example: :'a,'b d deletes all lines from the line marked as a to the line marked as b, inclusive.

Use :w newfile.txt to save to a new file called newfile.txt.
Use :set all to find out the value of all options set.
Use :8,16 co 32 to copy lines 8 through 16 to the spot after line 32.
Use :8,16 m 32 to move lines 8 through 16 to the spot after line 32.
If you have multiple files open for editing, use :n to go the next file in the sequence. If you are at the end of the sequence, use :rew to rewind to the beginning and start again with the first file in the sequence.
Use :args to list all the open files in order.

Until you have mastered everything on this page, you are not ready for Lesson Four.