Basic Editing Commands
**********************

We now give the basics of how to enter text, make corrections, and save the text in a file.  If this material is new to you, you might learn it more easily by running the Emacs learn-by-doing tutorial.  To do this, type Control-h t (help-with-tutorial).

Inserting Text
==============

To insert printing characters into the text you are editing, just type them.  This inserts the characters into the buffer at the cursor (that is, at point; see Point).  The cursor moves forward.  Any characters after the cursor move forward too.  If the text in the buffer is FOOBAR, with the cursor before the B, and you type XX, the result is FOOXXBAR, with the cursor still before the B.

To delete text you have just inserted, use DEL. DEL deletes the character BEFORE the cursor (not the one that the cursor is on top of or under; that is the character AFTER the cursor).  The cursor and all characters after it move backwards. Therefore, if you type a printing character and then type DEL, they cancel out.

To end a line and start typing a new one, type RET.  This inserts a newline character in the buffer.  If point is in the middle of a line, RET splits the line.  Typing DEL when the cursor is at the beginning of a line rubs out the newline before the line, thus joining the line with the preceding line.

Emacs automatically splits lines when they become too long, if you turn on a special mode called Auto Fill mode.  See Filling, for information on using Auto Fill mode.

Customization information: DEL, in most modes, runs the command delete-backward-char; RET runs the command newline, and self-inserting printing characters run the command self-insert, which inserts whatever character was typed to invoke it.  Some major modes rebind DEL to other commands.

Direct insertion works for printing characters and SPC, but other characters act as editing commands and do not insert themselves. If you need to insert a control character or a character whose code is above 200 octal, you must quote it by typing the character control-q (quoted-insert) first.  There are two ways to use C-q:

  * Control-q followed by any non-graphic character (even C-g) inserts that character.

  * Control-q followed by three octal digits inserts the character with the specified character code.

A numeric argument to C-q specifies how many copies of the quoted character should be inserted (see Arguments).

If you prefer to have text characters replace (overwrite) existing text instead of moving it to the right, you can enable Overwrite mode, a minor mode.  See Minor Modes.

Changing the Location of Point
==============================

To do more than insert characters, you have to know how to move point (see Point).  Here are a few of the available commands.

NOTE: Many of the following commands have two versions, one that uses the function keys (e.g. LEFT or END) and one that doesn't. The former versions may only be available on X terminals (i.e. not on TTY's), but the latter are available on all terminals.

C-a
HOME
     Move to the beginning of the line (beginning-of-line).

C-e
END
     Move to the end of the line (end-of-line).

C-f
RIGHT
     Move forward one character (forward-char).

C-b
LEFT
     Move backward one character (backward-char).

M-f
C-RIGHT
     Move forward one word (forward-word).

M-b
C-LEFT
     Move backward one word (backward-word).

C-n
DOWN
     Move down one line, vertically (next-line).  This command attempts to keep the horizontal position unchanged, so if you start in the middle of one line, you end in the middle of the next.  When on the last line of text, C-n creates a new line and moves onto it.

C-p
UP
     Move up one line, vertically (previous-line).

C-v
PGDN
     Move down one page, vertically (scroll-up).

M-v
PGUP
     Move up one page, vertically (scroll-down).

C-l
     Clear the frame and reprint everything (recenter).  Text moves on the frame to bring point to the center of the window.

M-r
     Move point to left margin on the line halfway down the frame or window (move-to-window-line).  Text does not move on the frame.  A numeric argument says how many screen lines down from the top of the window (zero for the top).  A negative argument counts from the bottom (-1 for the bottom).

C-t
     Transpose two characters, the ones before and after the cursor

     (transpose-chars).

M-<
C-HOME
     Move to the top of the buffer (beginning-of-buffer).  With numeric argument N, move to N/10 of the way from the top. See Arguments, for more information on numeric arguments.

M->
C-END
     Move to the end of the buffer (end-of-buffer).

M-x goto-char
     Read a number N and move the cursor to character number N. Position 1 is the beginning of the buffer.

M-g
     Read a number N and move cursor to line number N (goto-line).  Line 1 is the beginning of the buffer.

C-x C-n
     Use the current column of point as the semi-permanent goal column for C-n and C-p (set-goal-column).  Henceforth, those commands always move to this column in each line moved into, or as close as possible given the contents of the line.  This goal column remains in effect until canceled.

C-u C-x C-n
     Cancel the goal column.  Henceforth, C-n and C-p once again try to avoid changing the horizontal position, as usual.

If you set the variable track-eol to a non-nil value, C-n and C-p move to the end of the line when at the end of the starting line.  By default, track-eol is nil.

Erasing Text
============

DEL
     Delete the character before the cursor (delete-backward-char).

C-d
     Delete the character after the cursor (delete-char).

C-k
     Kill to the end of the line (kill-line).

M-d
     Kill forward to the end of the next word (kill-word).

M-DEL
     Kill back to the beginning of the previous word (backward-kill-word).

In contrast to the DEL key, which deletes the character before the cursor, Control-d deletes the character after the cursor, causing the rest of the text on the line to shift left.  If Control-d is typed at the end of a line, that line and the next line are joined.

To erase a larger amount of text, use Control-k, which kills a line at a time.  If you use C-k at the beginning or in the middle of a line, it kills all the text up to the end of the line.  If you use C-k at the end of a line, it joins that line and the next line.

See Killing, for more flexible ways of killing text.

Files
=====

The commands above are sufficient for creating and altering text in an Emacs buffer.  More advanced Emacs commands just make things easier.  But to keep any text permanently you must put it in a file.  Files are named units of text which are stored by the operating system and which you can retrieve by name.  To look at or use the contents of a file in any way, including editing the file with Emacs, you must specify the file name.

Consider a file named /usr/rms/foo.c.  To begin editing this file from Emacs, type:

     C-x C-f /usr/rms/foo.c RET

The file name is given as an argument to the command C-x C-f (find-file).  The command uses the minibuffer to read the argument.  You have to type RET to terminate the argument (see Minibuffer).

You can also use the Open... menu item from the File menu, then type the name of the file to the prompt.

Emacs obeys the command by visiting the file: it creates a buffer, copies the contents of the file into the buffer, and then displays the buffer for you to edit.  You can make changes in the buffer, and then save the file by typing C-x C-s (save-buffer) or choosing Save Buffer from the File menu. This makes the changes permanent by copying the altered contents of the buffer back into the file /usr/rms/foo.c.  Until then, the changes are only inside your Emacs buffer, and the file foo.c is not changed.

To create a file, visit the file with C-x C-f as if it already existed or choose Open... from the File menu and provide the name for the new file in the minibuffer.  Emacs will create an empty buffer in which you can insert the text you want to put in the file. When you save the buffer with C-x C-s, or by choosing Save Buffer from the File menu, the file is created.

To learn more about using files, see Files.

Help
====

If you forget what a key does, you can use the Help character (C-h) to find out: Type C-h k followed by the key you want to know about.  For example, C-h k C-n tells you what C-n does.  C-h is a prefix key; C-h k is just one of its subcommands (the command describe-key).  The other subcommands of C-h provide different kinds of help.  Type C-h three times to get a description of all the help facilities.  See Help.

Blank Lines
===========

Here are special commands and techniques for entering and removing blank lines.

C-o
     Insert one or more blank lines after the cursor (open-line).

C-x C-o
     Delete all but one of many consecutive blank lines (delete-blank-lines).

When you want to insert a new line of text before an existing line, you just type the new line of text, followed by RET.  If you prefer to create a blank line first and then insert the desired text, use the key C-o (open-line), which inserts a newline after point but leaves point in front of the newline.  Then type the text into the new line.  C-o F O O has the same effect as F O O RET, except for the final location of point.

To create several blank lines, type C-o several times, or give C-o an argument indicating how many blank lines to create. See Arguments, for more information.

If you have many blank lines in a row and want to get rid of them, use C-x C-o (delete-blank-lines).  If point is on a blank line which is adjacent to at least one other blank line, C-x C-o deletes all but one of the blank lines. If point is on a blank line with no other adjacent blank line, the sole blank line is deleted.  If point is on a non-blank line, C-x C-o deletes any blank lines following that non-blank line.

Continuation Lines
==================

If you add too many characters to one line without breaking with a RET, the line grows to occupy two (or more) screen lines, with a curved arrow at the extreme right margin of all but the last line.  The curved arrow indicates that the following screen line is not really a distinct line in the text, but just the continuation of a line too long to fit the frame.  You can use Auto Fill mode (see Filling) to have Emacs insert newlines automatically when a line gets too long.

Instead of continuation, long lines can be displayed by truncation. This means that all the characters that do not fit in the width of the frame or window do not appear at all.  They remain in the buffer, temporarily invisible.  Three diagonal dots in the last column (instead of the curved arrow inform you that truncation is in effect.

To turn off continuation for a particular buffer, set the variable truncate-lines to non-nil in that buffer. Truncation instead of continuation also happens whenever horizontal scrolling is in use, and optionally whenever side-by-side windows are in use (see Windows).  Altering the value of truncate-lines makes it local to the current buffer; until that time, the default value is in effect.  The default is initially nil.  See Locals.

Cursor Position Information
===========================

If you are accustomed to other display editors, you may be surprised that Emacs does not always display the page number or line number of point in the mode line.  In Emacs, this information is only rarely needed, and a number of commands are available to compute and print it. Since text is stored in a way that makes it difficult to compute the information, it is not displayed all the time.

M-x what-page
     Print page number of point, and line number within page.

M-x what-line
     Print line number of point in the buffer.

M-=
     Print number of lines and characters in the current region (count-lines-region).

C-x =
     Print character code of character after point, character position of point, and column of point (what-cursor-position).

There are several commands for printing line numbers:

  * M-x what-line counts lines from the beginning of the file and prints the line number point is on.  The first line of the file is line number 1.  You can use these numbers as arguments to M-x goto-line.

  * M-x what-page counts pages from the beginning of the file, and counts lines within the page, printing both of them.  See Pages, for the command C-x l, which counts the lines in the current page.

  * M-= (count-lines-region) prints the number of lines in the region (see Mark).

The command C-x = (what-cursor-position) provides information about point and about the column the cursor is in. It prints a line in the echo area that looks like this:

     Char: x (0170)  point=65986 of 563027(12%)  column 44

(In fact, this is the output produced when point is before column 44 in the example.)

The two values after Char: describe the character following point, first by showing it and second by giving its octal character code.

point= is followed by the position of point expressed as a character count.  The front of the buffer counts as position 1, one character later as 2, and so on.  The next, larger number is the total number of characters in the buffer.  Afterward in parentheses comes the position expressed as a percentage of the total size.

column is followed by the horizontal position of point, in columns from the left edge of the window.

If the buffer has been narrowed, making some of the text at the beginning and the end temporarily invisible, C-x = prints additional text describing the current visible range.  For example, it might say:

     Char: x (0170)  point=65986 of 563025(12%) <65102 - 68533>  column 44

where the two extra numbers give the smallest and largest character position that point is allowed to assume.  The characters between those two positions are the visible ones.  See Narrowing.

If point is at the end of the buffer (or the end of the visible part), C-x = omits any description of the character after point. The output looks like

     point=563026 of 563025(100%)  column 0

Numeric Arguments
=================

Any Emacs command can be given a numeric argument.  Some commands interpret the argument as a repetition count.  For example, giving an argument of ten to the key C-f (the command forward-char, move forward one character) moves forward ten characters.  With these commands, no argument is equivalent to an argument of one.  Negative arguments are allowed.  Often they tell a command to move or act backwards.

If your keyboard has a META key (labelled with a diamond on Sun-type keyboards and labelled Alt on some other keyboards), the easiest way to specify a numeric argument is to type digits and/or a minus sign while holding down the the META key.  For example,

     M-5 C-n

moves down five lines.  The characters Meta-1, Meta-2, and so on, as well as Meta--, do this because they are keys bound to commands (digit-argument and negative-argument) that are defined to contribute to an argument for the next command.

Another way of specifying an argument is to use the C-u (universal-argument) command followed by the digits of the argument. With C-u, you can type the argument digits without holding down shift keys.  To type a negative argument, start with a minus sign. Just a minus sign normally means -1.  C-u works on all terminals.

C-u followed by a character which is neither a digit nor a minus sign has the special meaning of ``multiply by four''.  It multiplies the argument for the next command by four.  C-u twice multiplies it by sixteen.  Thus, C-u C-u C-f moves forward sixteen characters.  This is a good way to move forward ``fast'', since it moves about 1/5 of a line in the usual size frame.  Other useful combinations are C-u C-n, C-u C-u C-n (move down a good fraction of a frame), C-u C-u C-o (make ``a lot'' of blank lines), and C-u C-k (kill four lines).

Some commands care only about whether there is an argument and not about its value.  For example, the command M-q (fill-paragraph) with no argument fills text; with an argument, it justifies the text as well. (see Filling, for more information on M-q.)  Just C-u is a handy way of providing an argument for such commands.

Some commands use the value of the argument as a repeat count, but do something peculiar when there is no argument.  For example, the command C-k (kill-line) with argument N kills N lines, including their terminating newlines.  But C-k with no argument is special: it kills the text up to the next newline, or, if point is right at the end of the line, it kills the newline itself.  Thus, two C-k commands with no arguments can kill a non-blank line, just like C-k with an argument of one.  (see Killing, for more information on C-k.)

A few commands treat a plain C-u differently from an ordinary argument.  A few others may treat an argument of just a minus sign differently from an argument of -1.  These unusual cases will be described when they come up; they are always to make the individual command more convenient to use.