Write specific lines from a file to a new file.

Example to write lines 230 through 300 to a new file:
:230,300w filename.txt
General Startup
    To use vi: vi filename
    To exit vi and save changes: ZZ   or  :wq
    To exit vi without saving changes: :q!
    To enter vi command mode: [esc]

Counts
        A number preceding any vi command tells vi to repeat
    that command that many times.

Cursor Movement

    h       move left (backspace)

    j       move down

    k       move up

    l       move right (spacebar)

    [return]   move to the beginning of the next line

    $       last column on the current line

    0       move cursor to the first column on the
        current line

    ^       move cursor to first nonblank column on the
        current line

    w       move to the beginning of the next word or
        punctuation mark

    W       move past the next space

    b       move to the beginning of the previous word
        or punctuation mark

    B       move to the beginning of the previous word,
        ignores punctuation

        e       end of next word or punctuation mark

        E       end of next word, ignoring punctuation

        H       move cursor to the top of the screen 

        M       move cursor to the middle of the screen

        L       move cursor to the bottom of the screen 

Screen Movement

       G        move to the last line in the file

       xG       move to line x

       z+       move current line to top of screen

       z        move current line to the middle of screen

       z-       move current line to the bottom of screen

       ^F       move forward one screen

       ^B       move backward one line

       ^D       move forward one half screen

       ^U       move backward one half screen

       ^R       redraw screen
        ( does not work with VT100 type terminals )

       ^L       redraw screen
        ( does not work with Televideo terminals )

Inserting

       r        replace character under cursor with next
        character typed

       R        keep replacing character until [esc] is hit

       i        insert before cursor

       a        append after cursor

       A        append at end of line

       O        open line above cursor and enter append mode

Deleting

    x       delete character under cursor

    dd      delete line under cursor

        dw      delete word under cursor

        db      delete word before cursor

Copying Code

        yy      (yank)'copies' line which may then be put by
        the p(put) command. Precede with a count for
        multiple lines.

        :t.     will duplicate the line.

        :t 7    will copy it after line 7.

        :,+t0   will copy current and next line at the
        beginning of the file.

        :1,t$   will copy lines from beginning of the file
        to the current cursor position, to the end of the file.

Put Command
        brings back previous deletion or yank of lines,
    words, or characters

        P       bring back before cursor

        p       bring back after cursor

Find Commands

    ?       finds a word going backwards

    /       finds a word going forwards

        f       finds a character on the line under the
        cursor going forward

        F       finds a character on the line under the
        cursor going backwards

        t       find a character on the current line going
        forward and stop one character before it

    T       find a character on the current line going
        backward and stop one character before it

    ;  repeat last f, F, t, T

Find and Replace Commands

        :%s/hello/goodbye/g   find hello and replace with goodbye

        :%s/^\(.*\)\n\1$/g    delete duplicate lines

        :%s/\n/ /g            join lines together

Miscellaneous Commands

    .  repeat last command

    u  undo last command issued

    U  undoes all commands on one line

    xp deletes first character and inserts after
        second (swap)

    J  join current line with the next line

    ^G display current line number

    %  if at one parenthesis, will jump to its mate

    mx mark current line with character x

    'x find line marked with character x

    NOTE: Marks are internal and not written to the file.

Line Editor Mode
    Any commands from the line editor ex can be issued
    upon entering line mode.

    To enter: type ':'

    To exit: press[return] or [esc]

ex Commands
    For a complete list consult the
    UNIX Programmer's Manual

READING FILES
    copies (reads) filename after cursor in file
    currently editing

    :r filename

WRITE FILE
    :w     saves the current file without quitting
    :20,40w filename write the contents of the lines numbered 20 through 40 to
    a new file named filename
MOVING

    :# move to line #

    :$ move to last line of file

SHELL ESCAPE
    executes 'cmd' as a shell command.

    :!'cmd'

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