A Beginner's guide to vi and ex

Using vi
Beginning Your Editing Session 
   To edit a file                       vi [ filename ]
   To recover an editing session        vi -r [ filename ]

Notes on vi commands and modal editing 

 All vi commands are entered in command mode. To enter command mode, press the ESC key. Some vi commands cause vi to enter another mode. For example, the i (insert command) causes vi to enter insert mode after which all keystrokes are inserted as text. To return to command mode from insert mode, press the ESC key. The :set showmode command will cause vi to display the current editing mode in the lower right corner of the editing screen. 

Controlling The Screen Display of Your Session 
   Repaint the current screen           {ctrl-l}
   Display line #, # of lines, etc..    {ctrl-g}

Moving the Cursor 
   Beginning of current line            0 or ^
   Beginning of first screen line       H
   Beginning of last screen line        L
   Beginning of middle screen line      M
   Down one line                        j, {return}, +
   End of current line                  $
   Left one character                   h, {ctrl-h}
   Left to beggining of word            b, B
   Right one character                  l, {space}
   Right to end of word                 e, E
   Right to beginning of word           w, W
   Up one line                          k, -
   Beginning of next sentence           )
   Beginning of previous sentence       (

Paging Through Text 
   Back one screen                      {ctrl-b}
   Down half a screen                   {ctrl-d}
   Down one screen                      {ctrl-f}
   Forware to end of file               G
   Move cursor to specified line        line no. G
   Up half a screen                     {ctrl-j}

Special Pattern Characters 
   Beginning of line                            ^
   End of line                                  $
   Any character except newline                 .
   Any number of the preceding character        *
   Any set of characters (except newline)       .*

Searching Through Text 
   Backward for pattern                         ?pattern
   Forward for pattern                          /pattern
   Repeat previous search                       n
   Reverse direction of previous search         N

   Show *all* lines containing pattern          :beg,endg/pattern/p
   :1,$g/compiler/p Will print all lines with the pattern compiler.

   Substitute patt2 for all patt1 found.        :beg,ends/patt1/patt2/g
   :%s/notfound/found/g Will change all occurences of notfound to found.

Creating Text 
   Append text after cursor             a
   Append text after end of line        A
   Insert text before cursor            i
   Insert text at beginning of line     I
   Open new line after current line     o
   Open new line before current line    O
   Take next character literally
    (i.e. control characters...)
    and display it                      {ctrl-v}

Modifying Text 
   Change current word                  cw, cW
   Change current line (cursor to end)  C
   Delete character (cursor forward)    x
   Delete character (before cursor)     X
   Delete word                          dw, dW
   Delete line                          dd
   Delete text to end of line           D
   Duplicate text                       (use yank and put)
   Join current line with next line     J
   Move text                            (use delete and put)
   Put buffer text after/below cursor   p
   Put buffer text before/above cursor  P
   Repeat last modification command     .
   Replace current character            r
   Replace text to end of line          R
   Substitute text for character        s
   Undo your previous command           u
   Transpose characters                 xp
   Yank (copy) word into buffer         yw
   Yank (copy) current line into buffer Y

Making Corrections During Text Insertions 
   Overwrite last character             {delete}
   Overwrite last word                  {ctrl-w}

Ending Your Editing Sessions 
   Quit (no changes made)               :q
   Quit and save changes                ZZ, :wq
   Quit and discard changes             :q!

Using ex Commands From Within vi 
   Copy specified lines                 :co, t
   Display line numbers                 :set nu
   Disable display of line numbers      :set nonu
   Move lines after specified line      :m
   Read file in after specified line    :r filename
   Review current editor options        :set 
   Review editor options                :set all
   Set new editor option                :set option
   Write changes to original file       :w
   Write to specified file              :w filename
   Force write to a file                :w! filename

Some Useful ex commands for use in vi

 Some useful set options for your ~/.exrc file: 
   :set all             Display all Set options
   :set autoindent      Automagically indent following lines to the indentation
                          of previous line.
   :set ignorecase      Ignore case during pattern matching.
   :set list            Show special characters in the file.
   :set number          Display line numbers.
   :set shiftwidth=n    Width for shifting operators << and >>
   :set showmode        Display mode when in Insert, Append, or Replace mode.
   :set wrapmargin=n    Set right margin 80-n for autowrapping lines 
                          (inserting newlines).  0 turns it off.