The Organization of the Screen
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On a text-only terminal, the Emacs display occupies the whole screen.  On a graphical display, such as on GNU/Linux using the X Window System, Emacs creates its own windows to use.  We use the term frame to mean the entire text-only screen or an entire system-level window used by Emacs.  Emacs uses both kinds of frames, in the same way, to display your editing.  Emacs normally starts out with just one frame, but you can create additional frames if you wish. See Frames.

When you start Emacs, the main central area of the frame, all except for the top and bottom and sides, displays the text you are editing. This area is called the window.  At the top there is normally a menu bar where you can access a series of menus; then there may be a tool bar, a row of icons that perform editing commands if you click on them.  Below this, the window begins, often with a scroll bar on one side.  Below the window comes the last line of the frame, a special echo area or minibuffer window, where prompts appear and you enter information when Emacs asks for it.  See following sections for more information about these special lines.

You can subdivide the window horizontally or vertically to make multiple text windows, each of which can independently display some file or text (see Windows).  In this manual, the word ``window'' refers to the initial large window if not subdivided, or any one of the multiple windows you have subdivided it into.

At any time, one window is the selected window.  On graphical displays, the selected window normally shows a more prominent cursor (usually solid and blinking) while other windows show a weaker cursor (such as a hollow box).   Text terminals have just one cursor, so it always appears in the selected window.

Most Emacs commands implicitly apply to the text in the selected window; the text in unselected windows is mostly visible for reference.  However, mouse commands generally operate on whatever window you click them in, whether selected or not.  If you use multiple frames on a graphical display, then giving the input focus to a particular frame selects a window in that frame.

Each window's last line is a mode line, which describes what is going on in that window.  It appears in different color and/or a ``3D'' box if the terminal supports them; its contents normally begin with --:--  *scratch* when Emacs starts.  The mode line displays status information such as what buffer is being displayed above it in the window, what major and minor modes are in use, and whether the buffer contains unsaved changes.

Point
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Within Emacs, the active cursor shows the location at which editing commands will take effect.  This location is called point. Many Emacs commands move point through the text, so that you can edit at different places in it.  You can also place point by clicking mouse button 1 (normally the left button).

While the cursor appears to be on a character, you should think of point as between two characters; it points before the character that appears under the cursor.  For example, if your text looks like frob with the cursor over the b, then point is between the o and the b.  If you insert the character ! at that position, the result is fro!b, with point between the ! and the b.  Thus, the cursor remains over the b, as before.

Sometimes people speak of ``the cursor'' when they mean ``point,'' or speak of commands that move point as ``cursor motion'' commands.

If you are editing several files in Emacs, each in its own buffer, each buffer has its own point location.  A buffer that is not currently displayed remembers its point location in case you display it again later.  When Emacs displays multiple windows, each window has its own point location.  If the same buffer appears in more than one window, each window has its own point position in that buffer, and (when possible) its own cursor.

A text-only terminal has just one cursor, in the selected window. The other windows do not show a cursor, even though they do have their own position of point.  When Emacs updates the screen on a text-only terminal, it has to put the cursor temporarily at the place the output goes.  This doesn't mean point is there, though.  Once display updating finishes, Emacs puts the cursor where point is.

On graphical displays, Emacs shows a cursor in each window; the selected window's cursor is solid and blinking, and the other cursors are just hollow.  Thus, the most prominent cursor always shows you the selected window, on all kinds of terminals.

See Cursor Display, for customizable variables that control display of the cursor or cursors.

The term ``point'' comes from the character ., which was the command in TECO (the language in which the original Emacs was written) for accessing the value now called ``point.''

The Echo Area
=============

The line at the bottom of the frame (below the mode line) is the echo area.  It is used to display small amounts of text for various purposes.

Echoing means displaying the characters that you type.  At the command line, the operating system normally echoes all your input. Emacs handles echoing differently.

Single-character commands do not echo in Emacs, and multi-character commands echo only if you pause while typing them.  As soon as you pause for more than a second in the middle of a command, Emacs echoes all the characters of the command so far.  This is to prompt you for the rest of the command.  Once echoing has started, the rest of the command echoes immediately as you type it.  This behavior is designed to give confident users fast response, while giving hesitant users maximum feedback.  You can change this behavior by setting a variable (see Display Custom).

If a command cannot do its job, it may display an error message in the echo area.  Error messages are accompanied by beeping or by flashing the screen.  The error also discards any input you have typed ahead.

Some commands display informative messages in the echo area.  These messages look much like error messages, but they are not announced with a beep and do not throw away input.  Sometimes the message tells you what the command has done, when this is not obvious from looking at the text being edited.  Sometimes the sole purpose of a command is to show you a message giving you specific information---for example, C-x = (hold down CTRL and type x, then let go of CTRL and type =) displays a message describing the character position of point in the text and its current column in the window.  Commands that take a long time often display messages ending in ... while they are working, and add done at the end when they are finished.  They may also indicate progress with percentages.

Echo-area informative messages are saved in an editor buffer named *Messages*.  (We have not explained buffers yet; see Buffers, for more information about them.)  If you miss a message that appears briefly on the screen, you can switch to the *Messages* buffer to see it again.  (Successive progress messages are often collapsed into one in that buffer.)

The size of *Messages* is limited to a certain number of lines.  The variable message-log-max specifies how many lines. Once the buffer has that many lines, adding lines at the end deletes lines from the beginning, to keep the size constant.  See Variables, for how to set variables such as message-log-max.

The echo area is also used to display the minibuffer, a window where you can input arguments to commands, such as the name of a file to be edited.  When the minibuffer is in use, the echo area begins with a prompt string that usually ends with a colon; also, the cursor appears in that line because it is the selected window.  You can always get out of the minibuffer by typing C-g. See Minibuffer.

The Mode Line
=============

Each text window's last line is a mode line, which describes what is going on in that window.  The mode line starts and ends with dashes.  When there is only one text window, the mode line appears right above the echo area; it is the next-to-last line in the frame. On a text-only terminal, the mode line is in inverse video if the terminal supports that; on a graphics display, the mode line has a 3D box appearance to help it stand out.  The mode line of the selected window is highlighted if possible; see Optional Mode Line, for more information.

Normally, the mode line looks like this:

     -CS:CHR-FR  BUF      POS LINE   (MAJOR MINOR)------

This gives information about the window and the buffer it displays: the buffer's name, what major and minor modes are in use, whether the buffer's text has been changed, and how far down the buffer you are currently looking.

CH contains two stars ** if the text in the buffer has been edited (the buffer is ``modified''), or -- if the buffer has not been edited.  For a read-only buffer, it is %* if the buffer is modified, and %% otherwise.

R is @ if the default-directory for the current buffer is on a remote machine, or a hyphen otherwise.

FR gives the selected frame name (see Frames).  It appears only on text-only terminals.  The initial frame's name is F1.

BUF is the name of the window's buffer.  Usually this is the same as the name of a file you are editing.  See Buffers.

The buffer displayed in the selected window (the window with the cursor) is the current buffer, where editing happens.  When a command's effect applies to ``the buffer,'' we mean it does those things to the current buffer.

POS tells you whether there is additional text above the top of the window, or below the bottom.  If your buffer is small and it is all visible in the window, POS is All.  Otherwise, it is Top if you are looking at the beginning of the buffer, Bot if you are looking at the end of the buffer, or NN%, where NN is the percentage of the buffer above the top of the window. With Size Indication mode, you can display the size of the buffer as well.  See Optional Mode Line.

LINE is L followed by the current line number of point. This is present when Line Number mode is enabled (it normally is). You can display the current column number too, by turning on Column Number mode.  It is not enabled by default because it is somewhat slower.  See Optional Mode Line.

MAJOR is the name of the major mode in effect in the buffer.  A buffer can only be in one major mode at a time.  The major modes available include Fundamental mode (the least specialized), Text mode, Lisp mode, C mode, Texinfo mode, and many others.  See Major Modes, for details of how the modes differ and how to select them.

Some major modes display additional information after the major mode name.  For example, Rmail buffers display the current message number and the total number of messages.  Compilation buffers and Shell buffers display the status of the subprocess.

MINOR is a list of some of the minor modes that are turned on at the moment in the window's chosen buffer.  For example, Fill means that Auto Fill mode is on.  Abbrev means that Word Abbrev mode is on.  Ovwrt means that Overwrite mode is on. See Minor Modes, for more information.

Narrow means that the buffer being displayed has editing restricted to only a portion of its text.  (This is not really a minor mode, but is like one.)  See Narrowing.  Def means that a keyboard macro is being defined.  See Keyboard Macros.

In addition, if Emacs is inside a recursive editing level, square brackets ([...]) appear around the parentheses that surround the modes.  If Emacs is in one recursive editing level within another, double square brackets appear, and so on.  Since recursive editing levels affect Emacs globally, not just one buffer, the square brackets appear in every window's mode line or not in any of them. See Recursive Edit.

CS states the coding system used for the file you are editing. A dash indicates the default state of affairs: no code conversion, except for end-of-line translation if the file contents call for that. = means no conversion whatsoever.  Nontrivial code conversions are represented by various letters---for example, 1 refers to ISO Latin-1.  See Coding Systems, for more information.

On a text-only terminal, CS includes two additional characters which describe the coding system for keyboard input and the coding system for terminal output.  They come right before the coding system used for the file you are editing.

If you are using an input method, a string of the form I> is added to the beginning of CS; I identifies the input method.  (Some input methods show + or @ instead of >.)  See Input Methods.

When multibyte characters are not enabled, CS does not appear at all.  See Enabling Multibyte.

The colon after CS changes to another string in some cases. Emacs uses newline characters to separate lines in the buffer.  Some files use different conventions for separating lines: either carriage-return linefeed (the MS-DOS convention) or just carriage-return (the Macintosh convention).  If the buffer's file uses carriage-return linefeed, the colon changes to either a backslash (\) or (DOS), depending on the operating system.  If the file uses just carriage-return, the colon indicator changes to either a forward slash (/) or (Mac).  On some systems, Emacs displays (Unix) instead of the colon for files that use newline as the line separator.

See Optional Mode Line, to add other handy information to the mode line, such as the size of the buffer, the current column number of point, and whether new mail for you has arrived.

The mode line is mouse-sensitive; when you move the mouse across various parts of it, Emacs displays help text to say what a click in that place will do.  See Mode Line Mouse.

The Menu Bar
============

Each Emacs frame normally has a menu bar at the top which you can use to perform common operations.  There's no need to list them here, as you can more easily see them yourself.

On a graphical display, you can use the mouse to choose a command from the menu bar.  A right-arrow at the end of the menu item means it leads to a subsidiary menu; ... at the end means that the command invoked will read arguments (further input from you) before it actually does anything.

You can also invoke the first menu bar item by pressing F10 (to run the command menu-bar-open).  You can then navigate the menus with the arrow keys.  You select an item by pressing RET and cancel menu navigation with ESC.

To view the full command name and documentation for a menu item, type C-h k, and then select the menu bar with the mouse in the usual way (see Key Help).

On text-only terminals with no mouse, you can use the menu bar by typing M-` or F10 (these run the command tmm-menubar).  This lets you select a menu item with the keyboard.  A provisional choice appears in the echo area.  You can use the up and down arrow keys to move through the menu to different items, and then you can type RET to select the item.

Each menu item also has an assigned letter or digit which designates that item; it is usually the initial of some word in the item's name. This letter or digit is separated from the item name by =>.  You can type the item's letter or digit to select the item.

Some of the commands in the menu bar have ordinary key bindings as well; one such binding is shown in parentheses after the item itself.