Aborting Aborting means
getting out of a recursive edit (q.v.). The commands C-] and M-x top-level
are used for this. See section Quitting and Aborting. Alt Alt is the name of a
modifier bit which a keyboard input character may have.
To make a character Alt,
type it while holding down the ALT key. Such characters are given names that
start with Alt- (usually written A-
for short). (Note that many terminals have a key labeled ALT which is really a META
key.) See section Kinds of User Input.
Auto Fill Mode Auto Fill mode is a minor mode in which text that you insert is automatically broken into lines
of fixed width. See section Filling Text.
Auto Saving Auto saving
is the practice of saving the contents of an Emacs buffer in a specially-named file, so that the information
will not be lost if the buffer is lost due to a system error or user error.
See section Auto-Saving: Protection Against Disasters.
Backup File A backup file records the contents that a file
had before the current editing session. Emacs makes backup files automatically to help you
track down or cancel changes you later regret making. See section Backup Files.
Balance Parentheses Emacs can balance parentheses manually
or automatically. Manual balancing is done by the commands to move over balanced
expressions (see section Lists and Sexps). Automatic
balancing is done by blinking or highlighting the
parenthesis that matches one just inserted (see section Automatic
Display Of Matching Parentheses).
Bind To bind a key
sequence means to give it a binding (q.v.). See section Changing Key Bindings Interactively.
Binding A key sequence gets its meaning in Emacs by having
a binding, which is a command
(q.v.), a Lisp function that is run when the user types that sequence. See section Keys and Commands. Customization
often involves rebinding a character to a different command function. The bindings of all key sequences are
recorded in the keymaps (q.v.). See section Keymaps.
Blank Lines Blank lines are lines that contain only whitespace. Emacs has several commands for operating on
the blank lines in the buffer.
Buffer The buffer is
the basic editing unit; one buffer corresponds to one text being edited. You can have several buffers, but at
any time you are editing only one, the `selected' buffer,
though several can be visible when you are using multiple windows (q.v.). Most buffers are
visiting (q.v.) some file. See section Using Multiple Buffers.
Buffer Selection History Emacs keeps a buffer selection
history which records how recently each Emacs buffer
has been selected. This is used for choosing a buffer
to select. See section Using Multiple Buffers.
Button Down Event A button down event is the kind of input
event generated right away when you press a mouse button. See section Rebinding Mouse Buttons.
C- C- in the name of a character is an abbreviation for Control. See section Kinds of User Input.
C-M- C-M- in the name of a character is an abbreviation for Control-Meta. See section Kinds of
User Input.
Case Conversion Case conversion means changing text from upper case to lower case or vice versa. See
section Case Conversion Commands, for the commands for
case conversion.
Character Characters form the contents of an Emacs buffer; see section Character
Set for Text. Also, key sequences (q.v.) are usually made up of characters (though
they may include other input events as well). See section Kinds
of User Input.
Click Event A click event is the kind of input event
generated when you press a mouse button and release it without moving the mouse. See
section Rebinding Mouse Buttons.
Command A command is a
Lisp function specially defined to be able to serve as a key binding
in Emacs. When you type a key sequence (q.v.), its binding
(q.v.) is looked up in the relevant keymaps (q.v.) to find the command to run. See section Keys
and Commands.
Command Name A command
name is the name of a Lisp symbol which is a command
(see section Keys and Commands). You can invoke any command by its name using M-x (see section Running Commands by Name).
Comment A comment is text in a program which is intended only for humans
reading the program, and which is marked specially so that it will be ignored when the
program is loaded or compiled. Emacs offers special commands for creating, aligning and killing comments. See section Manipulating Comments.
Compilation Compilation
is the process of creating an executable program from source code. Emacs has commands for
compiling files of Emacs Lisp code (see section 'Byte Compilation'
in the Emacs Lisp Reference Manual) and programs in C and other languages
(see section Running Compilations under Emacs).
Complete Key A complete key is a key sequence which fully
specifies one action to be performed by Emacs. For example, X and C-f
and C-x m are complete keys. Complete keys derive their meanings from being
bound (q.v.) to commands (q.v.). Thus, X is conventionally bound to a command to insert X in the buffer; C-x m is conventionally bound to a command to begin composing a mail message. See
section Keys.
Completion Completion
is what Emacs does when it automatically fills out an abbreviation for a name into the
entire name. Completion is done for minibuffer (q.v.) arguments when the set of possible
valid inputs is known; for example, on command names, buffer names, and file names. Completion occurs when TAB, SPC or RET
is typed. See section Completion.
Continuation Line When a line of text is longer than the width of the window, it takes up more than one screen line when
displayed. We say that the text line is continued, and
all screen lines used for it after the first are called continuation lines. See section Basic Editing Commands.
Control Character ASCII characters with octal codes 0
through 037, and also code 0177, do not have graphic images assigned to them. These are
the Control characters. To type a Control character,
hold down the CTRL key and type the corresponding non-Control character. RET, TAB, ESC,
LFD and DEL are all control characters. See section Kinds of User Input.
When you are using the X Window System, every
non-control character has a corresponding control character variant.
Copyleft A copyleft is
a notice giving the public legal permission to redistribute a program or other work of
art. Copylefts are used by left-wing programmers to give people equal rights, just as
copyrights are used by right-wing programmers to gain power over other people.
The particular form of copyleft used by the GNU
project is called the GNU General Public License. See section GNU
GENERAL PUBLIC LICENSE.
Current Buffer The current buffer
in Emacs is the Emacs buffer on which most editing
commands operate. You can select any Emacs buffer as
the current one. See section Using Multiple Buffers.
Current Line The line point
is on (see section Point).
Current Paragraph The paragraph
that point is in. If point
is between paragraphs, the current paragraph is the
one that follows point. See section Paragraphs.
Current Defun The defun
(q.v.) that point is in. If point is between defuns, the current defun is the one that follows point. See section Defuns.
Cursor The cursor is
the rectangle on the screen which indicates the
position called point (q.v.) at which insertion and deletion
takes place. The cursor is on or under the character that follows point.
Often people speak of `the cursor' when, strictly
speaking, they mean `point'. See section Basic Editing Commands.
Customization Customization
is making minor changes in the way Emacs works. It is often done by setting variables (see
section Variables) or by rebinding key sequences (see
section Keymaps).
Default Argument The default for an argument is the value
that will be assumed if you do not specify one. When the minibuffer
is used to read an argument, the default argument is used if you just type RET.
See section The Minibuffer.
Default Directory When you specify a file name that does
not start with / or ~, it is interpreted relative to the current
buffer's default directory.
See section Minibuffers for File Names.
Defun A defun is a list at the top level of parenthesis or bracket structure
in a program. It is so named because most such lists in Lisp programs are calls to the
Lisp function defun. See section Defuns.
DEL DEL is a character that runs the command
to delete one character of text. See section Basic
Editing Commands.
Deletion Deletion means
erasing text without copying it into the kill ring
(q.v.). The alternative is killing (q.v.). See section Deletion and Killing.
Deletion of Files Deleting a file means erasing it from
the file system. See section Miscellaneous File Operations.
Deletion of Messages Deleting a message means flagging it to be eliminated from your mail file. Until you expunge (q.v.) the Rmail file, you
can still undelete the messages you have deleted. See section Deleting Messages.
Deletion of Windows Deleting a window means eliminating it from the screen. Other
windows expand to use up the space. The deleted window
can never come back, but no actual text is thereby
lost. See section Multiple Windows.
Directory File directories are named collections in the
file system, within which you can place individual files or subdirectories. See section File Directories.
Dired Dired is the
Emacs facility that displays the contents of a file directory
and allows you to ``edit the directory'', performing
operations on the files in the directory. See section Dired, the Directory Editor.
Disabled Command A disabled command
is one that you may not run without special confirmation. The usual reason for disabling a
command is that it is confusing for beginning users.
See section Disabling Commands.
Down Event Short for `button down event'.
Drag Event A drag event is the kind of input event
generated when you press a mouse button, move the mouse, and then release the button. See
section Rebinding Mouse Buttons.
Dribble File A file into which Emacs writes all the
characters that the user types on the keyboard. Dribble files are used to make a record
for debugging Emacs bugs. Emacs does not make a dribble file unless you tell it to. See
section Reporting Bugs.
Echo Area The echo area is the bottom line of the screen,
used for echoing the arguments to commands, for asking
questions, and printing brief messages (including error
messages). The messages are stored in the buffer *Messages*
so you can review them later. See section The Echo Area.
Echoing Echoing is
acknowledging the receipt of commands by displaying them (in the echo area). Emacs never
echoes single-character key sequences; longer key
sequences echo only if you pause while typing them.
Error An error occurs
when an Emacs command cannot execute in the current
circumstances. When an error occurs, execution of the command stops (unless the command
has been programmed to do otherwise) and Emacs reports the error
by printing an error message
(q.v.). Type-ahead is discarded. Then Emacs is ready to read another editing command.
Error Message An error message is a single line of output displayed by Emacs when
the user asks for something impossible to do (such as, killing
text forward when point
is at the end of the buffer). They appear in the echo
area, accompanied by a beep.
ESC ESC is a character used as a prefix for typing Meta characters on keyboards lacking a META
key. Unlike the META key (which, like the SHIFT key, is held down
while another character is typed), the ESC
key is pressed once and applies to the next character
typed.
Expunging Expunging an
Rmail file or Dired buffer
means really discarding the messages or files you have previously flagged for deletion.
File Name A file name is a name that refers to a file.
File names may be relative or absolute; the meaning of a relative file name depends on the
current directory, but an absolute file name refers to
the same file regardless of which directory is current.
On GNU and Unix systems, an absolute file name starts with a slash (the root directory) or with ~/ or ~user/
(a home directory).
Some people use the term ``pathname'' for file names, but we do not; we use the word
``path'' only in the term ``search path'' (q.v.).
File Name Component A file name component names a file
directly within a particular directory. On GNU and Unix
systems, a file name is a sequence of file name components, separated by slashes. For
example, foo/bar is a file name containing two components, foo and bar;
it refers to the file named bar in the directory
named foo in the current directory.
Fill Prefix The fill prefix is a string that should be expected at the beginning of each
line when filling is done. It is not regarded as part
of the text to be filled. See section Filling Text.
Filling Filling text means shifting text
between consecutive lines so that all the lines are approximately the same length. See
section Filling Text.
Formatted Text Formatted text
is text that displays with formatting information
while you edit. Formatting information includes fonts, colors, and specified margins. See
section Editing Formatted Text.
Frame A frame is a
rectangular cluster of Emacs windows. Emacs starts out with one frame, but you can create more. You can subdivide each frame into Emacs windows (q.v.). When you are using X
windows, all the frames can be visible at the same time. See section Frames and X Windows.
Function Key A function key is a key on the keyboard that
sends input but does not correspond to any character.
See section Rebinding Function Keys.
Global Global means
`independent of the current environment; in effect throughout Emacs'. It is the opposite
of local (q.v.). Particular examples of the use of `global' appear below.
Global Abbrev A global
definition of an abbrev (q.v.) is effective in all major
modes that do not have local (q.v.) definitions for the
same abbrev. See section Abbrevs.
Global Keymap The global
keymap (q.v.) contains key bindings that are in effect
except when overridden by local key bindings in a major
mode's local keymap
(q.v.). See section Keymaps.
Global Mark Ring The global
mark ring records the series of buffers you have
recently set a mark in. In many cases you can use this
to backtrack through buffers you have been editing in, or in which you have found tags.
See section The Global Mark Ring.
Global Substitution Global
substitution means replacing each occurrence of one string
by another string through a large amount of text. See section Replacement
Commands.
Global Variable The global
value of a variable (q.v.) takes effect in all buffers
that do not have their own local (q.v.) values for the variable. See section Variables.
Graphic Character Graphic characters are those assigned
pictorial images rather than just names. All the non-Meta
(q.v.) characters except for the Control (q.v.) characters are graphic characters. These
include letters, digits, punctuation, and spaces; they do not include RET or ESC.
In Emacs, typing a graphic character inserts that character (in ordinary editing modes). See section Basic Editing Commands.
Highlighting Highlighting
text means displaying it with a different foreground
and/or background color to make it stand out from the rest of the text in the buffer.
Hardcopy Hardcopy means
printed output. Emacs has commands for making printed listings of text in Emacs buffers. See section Hardcopy Output.
HELP You can type HELP at any time
to ask what options you have, or to ask what any command
does. The character HELP is really C-h.
See section Help.
Hyper Hyper is the name
of a modifier bit which a keyboard input character may
have. To make a character Hyper, type it while holding down the HYPER
key. Such characters are given names that start with Hyper-
(usually written H- for short). See section Kinds
of User Input.
Inbox An inbox is a
file in which mail is delivered by the operating
system. Rmail transfers mail from inboxes to Rmail
files (q.v.) in which the mail is then stored
permanently or until explicitly deleted. See section Rmail
Files and Inboxes.
Indentation Indentation
means blank space at the beginning of a line. Most programming languages have conventions
for using indentation to illuminate the structure of
the program, and Emacs has special commands to adjust indentation.
See section Indentation.
Indirect Buffer An indirect buffer
is a buffer that shares the text of another buffer,
called its base buffer. See section Indirect Buffers.
Input Event An input event represents, within Emacs, one
action taken by the user on the terminal. Input events include typing characters, typing
function keys, pressing or releasing mouse buttons, and switching between Emacs frames.
See section Kinds of User Input.
Insertion Insertion
means copying text into the buffer, either from the keyboard or from some other place
in Emacs.
Justification Justification
means adding extra spaces to lines of text to make
them come exactly to a specified width. See section Filling
Text.
Keyboard Macro Keyboard macros are a way of defining new
Emacs commands from sequences of existing ones, with no need to write a Lisp program. See
section Keyboard Macros.
Key Sequence A key sequence (key, for short) is a sequence
of input events (q.v.) that are meaningful as a single unit. If the key sequence is enough
to specify one action, it is a complete key (q.v.); if it is not enough, it is a prefix
key (q.v.). See section Keys.
Keymap The keymap is
the data structure that records the bindings (q.v.) of key sequences to the commands that
they run. For example, the global keymap binds the character
C-n to the command function next-line.
See section Keymaps.
Keyboard Translation Table The keyboard translation table
is an array that translates the character codes that
come from the terminal into the character codes that
make up key sequences. See section Keyboard Translations.
Kill Ring The kill ring is where all text you have killed recently is saved. You can reinsert
any of the killed text still in the ring; this is
called yanking (q.v.). See section Yanking.
Killing Killing means
erasing text and saving
it on the kill ring so it can be yanked (q.v.) later. Some other systems call this
``cutting''. Most Emacs commands to erase text do killing, as opposed to deletion
(q.v.). See section Deletion and Killing.
Killing Jobs Killing a
job (such as, an invocation of Emacs) means making it cease to exist. Any data within it,
if not saved in a file, is lost. See section Exiting Emacs.
List A list is,
approximately, a text string
beginning with an open parenthesis and ending with the matching close parenthesis. In C
mode and other non-Lisp modes, groupings surrounded by other kinds of matched delimiters
appropriate to the language, such as braces, are also considered lists. Emacs has special
commands for many operations on lists. See section Lists and
Sexps.
Local Local means `in
effect only in a particular context'; the relevant kind of context is a particular
function execution, a particular buffer, or a
particular major mode. It is the opposite of `global'
(q.v.). Specific uses of `local' in Emacs terminology
appear below.
Local Abbrev A local abbrev definition is effective only if a particular major
mode is selected. In that major mode, it overrides any global
definition for the same abbrev. See section Abbrevs.
Local Keymap A local keymap is used in a particular major mode; the key
bindings (q.v.) in the current local keymap override global
bindings of the same key sequences. See section Keymaps.
Local Variable A local
value of a variable (q.v.) applies to only one buffer. See section Local
Variables.
M- M- in the name of a character is an abbreviation for META, one of
the modifier keys that can accompany any character. See
section Kinds of User Input.
M-C- M-C- in the name of a character is an abbreviation for Control-Meta; it means the same thing as C-M-. If your
terminal lacks a real META key, you type a Control-Meta character by
typing ESC and then typing the corresponding Control character. See section Kinds
of User Input.
M-x M-x is the key sequence which is
used to call an Emacs command by name. This is how you
run commands that are not bound to key sequences. See section Running
Commands by Name.
Mail Mail means
messages sent from one user to another through the computer system, to be read at the
recipient's convenience. Emacs has commands for composing and sending mail, and for reading and editing the mail you have received. See section Sending Mail. See section Reading
Mail with Rmail, for how to read mail.
Major Mode The Emacs major modes are a mutually exclusive
set of options, each of which configures Emacs for editing a certain sort of text. Ideally, each programming language has its own
major mode. See section Major Modes.
Mark The mark points to
a position in the text. It specifies one end of the region (q.v.), point
being the other end. Many commands operate on all the text
from point to the mark.
Each buffer has its own mark.
See section The Mark and the Region.
Mark Ring The mark ring
is used to hold several recent previous locations of the mark,
just in case you want to move back to them. Each buffer
has its own mark ring; in addition, there is a single global mark ring
(q.v.). See section The Mark Ring.
Menu Bar The menu bar is the line at the top of an Emacs frame. It contains words you can click on with the mouse
to bring up menus. The menu bar feature is supported only with X. See section Menu Bars.
Message See `mail'.
Meta Meta is the name
of a modifier bit which a command character may have. It is present in a character if the character
is typed with the META key held down. Such characters are given names that
start with Meta- (usually written M-
for short). For example, M- is typed by holding down META and at the same time
typing (which itself is done, on most terminals, by holding down SHIFT and
typing ,). See section Kinds of User Input.
Meta Character A Meta character is one whose character
code includes the Meta bit.
Minibuffer The minibuffer
is the window that appears when necessary inside the
echo area (q.v.), used for reading arguments to commands. See section The Minibuffer.
Minibuffer History The minibuffer
history records the text you have specified in the
past for minibuffer arguments, so you can conveniently
use the same text again. See section Minibuffer History.
Minor Mode A minor mode is an optional feature of Emacs
which can be switched on or off independently of all other features. Each minor mode has a
command to turn it on or off. See section Minor Modes.
Minor Mode Keymap A keymap
that belongs to a minor mode and is active when that mode is enabled. Minor mode keymaps
take precedence over the buffer's local keymap, just as
the local keymap
takes precedence over the global keymap. See section Keymaps.
Mode Line The mode line is the line at the bottom of each
window (q.v.), giving status information on the buffer displayed in that window.
See section The Mode Line.
Modified Buffer A buffer
(q.v.) is modified if its text has been changed since
the last time the buffer was saved (or since when it
was created, if it has never been saved). See section Saving
Files.
Moving Text Moving text
means erasing it from one place and inserting it in another. The usual way to move text by killing (q.v.)
and then yanking (q.v.). See section Deletion and Killing.
Named Mark A named mark
is a register (q.v.) in its role of recording a location in text so that you can move point
to that location. See section Registers.
Narrowing Narrowing
means creating a restriction (q.v.) that limits
editing in the current buffer to only a part of the text in the buffer. Text outside that part is inaccessible to the user until
the boundaries are widened again, but it is still there, and saving the file saves it all. See section Narrowing.
Newline Linefeed characters in the buffer terminate lines of text
and are therefore also called newlines. See section Character
Set for Text.
Numeric Argument A numeric argument is a number,
specified before a command, to change the effect of the
command. Often the numeric argument serves as a repeat
count. See section Numeric Arguments.
Option An option is a
variable (q.v.) that exists so that you can customize
Emacs by setting it to a new value. See section Variables.
Overwrite Mode Overwrite mode is a minor mode. When it is
enabled, ordinary text characters replace the existing
text after point
rather than pushing it to the right. See section Minor Modes.
Page A page is a unit
of text, delimited by formfeed characters (ASCII
control-L, code 014) coming at the beginning of a line. Some Emacs commands are provided
for moving over and operating on pages. See section Pages.
Paragraph Paragraphs are the medium-size unit of English text. There are special Emacs commands for moving over
and operating on paragraphs. See section Paragraphs.
Parsing We say that certain Emacs commands parse words or
expressions in the text being edited. Really, all they
know how to do is find the other end of a word or expression. See section The Syntax Table.
Point Point is the
place in the buffer at which insertion and deletion
occur. Point is considered to be between two
characters, not at one character. The terminal's cursor (q.v.) indicates the location of point. See section Basic
Editing Commands. Prefix Argument See `numeric
argument'.
Prefix Key A prefix key is a key sequence (q.v.) whose
sole function is to introduce a set of longer key sequences. C-x is an example
of prefix key; any two-character sequence starting with
C-x is therefore a legitimate key sequence. See section Keys.
Primary Rmail File Your primary Rmail file is the file
named RMAIL in your home directory. That's
where Rmail stores your incoming mail, unless you
specify a different file name. See section Reading Mail with
Rmail.
Primary Selection The primary selection is one particular X selection (q.v.); it is the selection that most X applications use for transferring text to and from other applications.
The Emacs kill commands set the primary selection
and the yank command uses the primary selection when appropriate. See section Deletion and Killing.
Prompt A prompt is text printed to ask the user for input. Displaying a prompt is called prompting. Emacs prompts always appear
in the echo area (q.v.). One kind of prompting happens when the minibuffer is used to read an argument (see section The Minibuffer); the echoing
which happens when you pause in the middle of typing a multi-character key sequence is also a kind of prompting (see
section The Echo Area).
Quitting Quitting
means canceling a partially typed command or a running command, using C-g. See section Quitting and Aborting.
Quoting Quoting means
depriving a character of its usual special
significance. In Emacs this is usually done with C-q. What constitutes special
significance depends on the context and on convention. For example, an ``ordinary'' character as an Emacs command
inserts itself; so in this context, a special character
is any character that does not normally insert itself
(such as DEL, for example), and quoting it
makes it insert itself as if it were not special. Not all contexts allow quoting. See section Basic
Editing Commands.
Read-Only Buffer A read-only buffer is one whose text
you are not allowed to change. Normally Emacs makes buffers read-only when they contain text which has a special significance to Emacs; for
example, Dired buffers. Visiting
a file that is write protected also makes a read-only buffer.
See section Using Multiple Buffers.
Rectangle A rectangle
consists of the text in a given range of columns on a
given range of lines. Normally you specify a rectangle
by putting point at one corner and putting the mark at the opposite corner. See section Rectangles.
Recursive Editing Level A recursive editing level is a
state in which part of the execution of a command
involves asking the user to edit some text. This text may or may not be the same as the text to which the command
was applied. The mode line indicates recursive editing levels with square brackets ([
and ]). See section Recursive Editing Levels.
Redisplay Redisplay
is the process of correcting the image on the screen to correspond to changes that have
been made in the text being edited. See section The Organization of the Screen.
Regexp See `regular expression'.
Region The region is
the text between point
(q.v.) and the mark (q.v.). Many commands operate on
the text of the region.
See section The Mark and the Region.
Registers Registers
are named slots in which text or buffer positions or rectangles can be saved for later use.
See section Registers.
Regular Expression A regular expression is a pattern that
can match various text strings; for example, l[0-9]+
matches l followed by one or more digits. See section Syntax of Regular Expressions.
Repeat Count See `numeric argument'.
Replacement See `global
substitution'.
Restriction A buffer's
restriction is the amount of text, at the beginning or the end of the buffer, that is temporarily inaccessible. Giving a buffer a nonzero amount of restriction
is called narrowing (q.v.). See section Narrowing.
RET RET is a character that in Emacs runs the command to insert a newline
into the text. It is also used to terminate most
arguments read in the minibuffer (q.v.). See section Kinds of User Input.
Rmail File An Rmail file is a file containing text in a special format used by Rmail for storing mail. See section Reading
Mail with Rmail.
Saving Saving a buffer means copying its text
into the file that was visited (q.v.) in that buffer.
This is the way text in files actually gets changed by
your Emacs editing. See section Saving Files.
Scroll Bar A scroll bar is a tall thin hollow box that
appears at the side of a window. You can use mouse
commands in the scroll bar to scroll the window. The
scroll bar feature is supported only with X. See section Scroll
Bars.
Scrolling Scrolling
means shifting the text in the Emacs window so as to see a different part of the buffer. See section Controlling
the Display.
Searching Searching
means moving point to the next occurrence of a
specified string or the next match for a specified
regular expression. See section Searching and Replacement.
Search Path A search path is a list of directory
names, to be used for searching for files for certain
purposes. For example, the variable load-path
holds a search path for finding Lisp library files. See section Libraries of Lisp Code for Emacs.
Secondary Selection The secondary selection is one particular X selection; some X applications can use it for
transferring text to and from other applications.
Emacs has special mouse commands for transferring text
using the secondary selection. See section Secondary Selection.
Selecting Selecting a
buffer means making it the current (q.v.) buffer. See section Using
Multiple Buffers.
Selection The X window
system allows an application program to specify named selections whose values are text. A program can also read the selections that other
programs have set up. This is the principal way of transferring text between window
applications. Emacs has commands to work with the primary (q.v.) selection and the secondary (q.v.) selection.
Self-Documentation Self-documentation is the feature of
Emacs which can tell you what any command does, or give
you a list of all commands related to a topic you
specify. You ask for self-documentation with the help character,
C-h. See section Help.
Sentences Emacs has commands for moving by or killing by sentences.
See section Sentences.
Sexp A sexp (short
for `s-expression') is the basic syntactic unit of Lisp in its textual form: either a list, or Lisp atom. Many Emacs commands operate on sexps.
The term `sexp' is generalized to languages other than
Lisp, to mean a syntactically recognizable expression. See section Lists and Sexps.
Simultaneous Editing Simultaneous editing means two users
modifying the same file at once. Simultaneous editing if not detected can cause one user
to lose his work. Emacs detects all cases of simultaneous editing and warns one of the
users to investigate. See section Protection against
Simultaneous Editing.
String A string is a
kind of Lisp data object which contains a sequence of characters. Many Emacs variables are
intended to have strings as values. The Lisp syntax for a string
consists of the characters in the string with a "
before and another " after. A " that is part of the string must be written as \" and a \
that is part of the string must be written as \\.
All other characters, including newline, can be
included just by writing them inside the string;
however, backslash sequences as in C, such as \n for newline or \241 using an octal character code, are allowed as well.
String Substitution See `global
substitution'.
Syntax Table The syntax table tells Emacs which
characters are part of a word, which characters balance each other like parentheses, etc.
See section The Syntax Table.
Super Super is the
name of a modifier bit which a keyboard input character
may have. To make a character Super, type it while holding down the SUPER
key. Such characters are given names that start with Super-
(usually written s- for short). See section Kinds
of User Input.
Tags Table A tags table is a file that serves as an index
to the function definitions in one or more other files. See section Tags Tables.
Termscript File A termscript file contains a record of
all characters sent by Emacs to the terminal. It is used for tracking down bugs in Emacs redisplay. Emacs does not make a termscript file unless
you tell it to. See section Reporting Bugs.
Text Two meanings (see section Commands for Human Languages):
- Data consisting of a sequence of characters, as opposed to binary numbers, images,
graphics commands, executable programs, and the like. The contents of an Emacs buffer are always text
in this sense.
- Data consisting of written human language, as opposed to programs, or following the
stylistic conventions of human language.
Top Level Top level is the normal state of Emacs, in
which you are editing the text of the file you have
visited. You are at top level whenever you are not in a recursive editing level (q.v.) or
the minibuffer (q.v.), and not in the middle of a command. You can get back to top level by aborting (q.v.) and quitting
(q.v.). See section Quitting and Aborting.
Transposition Transposing two units of text means putting each one into the place formerly
occupied by the other. There are Emacs commands to transpose two adjacent characters,
words, sexps (q.v.) or lines (see section Transposing Text).
Truncation Truncating text
lines in the display means leaving out any text on a
line that does not fit within the right margin of the window
displaying it. See also `continuation line'. See section Basic
Editing Commands.
Undoing Undoing means
making your previous editing go in reverse, bringing back the text that existed earlier in the editing session. See
section Undoing Changes.
Variable A variable
is an object in Lisp that can store an arbitrary value. Emacs uses some variables for
internal purposes, and has others (known as `options' (q.v.)) just so that you can set
their values to control the behavior of Emacs. The variables used in Emacs that you are
likely to be interested in are listed in the Variables Index in this manual. See section Variables, for information on variables.
Version Control Version control systems keep track of
multiple versions of a source file. They provide a more powerful alternative to keeping
backup files (q.v.). See section Version Control.
Visiting Visiting a
file means loading its contents into a buffer (q.v.)
where they can be edited. See section Visiting Files.
Whitespace Whitespace
is any run of consecutive formatting characters (space, tab, newline, and backspace).
Widening Widening is
removing any restriction (q.v.) on the current buffer; it is the opposite of narrowing (q.v.). See section Narrowing.
Window Emacs divides a frame
(q.v.) into one or more windows, each of which can display the contents of one buffer (q.v.) at any time. See section The Organization of the Screen, for basic information on how
Emacs uses the screen. See section Multiple Windows, for
commands to control the use of windows.
Word Abbrev Synonymous with `abbrev'.
Word Search Word search is searching for a sequence of words, considering the
punctuation between them as insignificant. See section Word
Search.
WYSIWYG WYSIWYG
stands for ``What you see is what you get.'' Emacs generally provides WYSIWYG editing for files of characters; in Enriched mode
(see section Editing Formatted Text), it provides WYSIWYG editing for files that include text formatting information.
Yanking Yanking means
reinserting text previously killed. It can be used to
undo a mistaken kill, or for copying or moving text.
Some other systems call this ``pasting''. See section Yanking.
