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@Comment[ Any (q.v.) at the end of a line must be followed by a @;]

@Unnumbered(Glossary)

@begin(description)

Aborting @\Aborting a recursive editing level (q.v.) means canceling the
command which invoked the recursive editing.  For example, if you
abort editing a message to be sent, the message is not sent.  Aborting
is done with the command C-].  @Note(Name="Aborting", Node="Quitting").

Altmode @\Altmode is a character, labelled Escape on some keyboards.
It is the bit prefix character (q.v.) used to enter Meta-characters when the
keyboard does not have a Meta (q.v.) key.  @Note(Node="Characters").  Also,
it delimits string arguments to extended commands.  @Note(Node="M-X",
Name="Extended Commands").

Balance Parentheses @\EMACS can balance parentheses manually or
automatically.  You can ask to move from one parenthesis to the
matching one.  @Note(Node="Lists").  When you insert a close
parenthesis, EMACS can show the matching open.
@Note(Node="Matching").

Bit Prefix Character @\A bit prefix character is a command which
combines with the next character typed to make one character.  They
are used for effectively typing commands which the keyboard being
used is not able to send.  For example, to use a Meta-character when
there is no Meta key on the keyboard, the bit prefix character Altmode
(q.v.) is needed.  @Note(IName="Bit Prefix", Node="Characters").

Buffer @\The buffer is the basic editing unit; one buffer corresponds
to one piece of text being edited.  You can have several buffers, but
at any time you are editing only one, the "selected" buffer, though
two can be visible when you are using two windows.
@Note(Node="Buffers").

C- @\C is an abbreviation for Control, in the name of a character.
@Note(IName="C-", Node="Characters").

C-M- @\C-M- is an abbreviation for Control-Meta, in the name of a
character.  @Note(IName="C-M-", Node="Characters").

Comment @\A comment is text in a program which is intended only for
humans reading the program, and is marked specially so that the
compiler will ignore it.  EMACS offers special commands for creating and
killing comments.  @Note(Node="Comments").

Command @\A command is a character or sequence of characters which,
when typed by the user, fully specifies one action to be performed by
EMACS.  For example, "X" and "Control-F" and "Meta-X Text Mode<cr>"
are commands.  @Note(IName="Command", Node="Characters").  Sometimes
the first character of a multi-character command is also considered a
command: M-X Text Mode<cr> is a command (an extended command), and M-X
is also a command (a command to read a function name and invoke the
function).  @Note(Name="Extended Commands", Node="M-X").

Completion @\Completion is what EMACS does when it automatically fills
out the beginning of an extended command name into the full name, or
as much of it as can be deduced for certain.  Completion occurs when
Altmode, Space or Return is typed.  @Note(IName="Completion",
Name="Extended Commands", Node="M-X").

Connected @\A character command in EMACS works by calling a function
which it is "connected" to.  Customization often involves connecting a
character to a different function.  See "Dispatch table".
@Note(IName="Connected", Node="Characters").

Continuation Line @\When a line of text is longer than the width of
the screen, it is displayed on more than one line of screen.  We say
that the line is continued, and that all screen lines used but the
first are called continuation lines.  @Note(IName="Continuation",
Name="Basic Editing", Node="Basic").

Control @\Control is the name of a bit which each command character
does or does not contain.  A character's name includes the word
Control if the Control bit is part of that character.  Ideally, this
means that the character is typed using the Control key: Control-A is
typed by typing "A" while holding down Control.  On most keyboards the
Control key works in only some cases; the rest of the time, a bit
prefix character (q.v.) must be used.  @Note(IName="Control",
Node="Characters").

Control-Character @\A Control character is a character which includes
the Control bit.

Control-X Command @\A Control-X command is a two-character command
whose first character is the prefix character Control-X.
@Note(IName="Control-X Command", Node="Characters").

<cr> @\<cr> stands for the carriage return character, in contexts where
the word "Return" might be confusing.  @Note(IName="<cr>",
Node="Characters").

CRLF @\CRLF stands for the sequence of two characters, carriage return
followed by linefeed, which is used to separate lines in files and
in text being edited in EMACS.  @Note(IName="CRLF", Node="Characters").

Cursor @\The cursor is the object on the screen which indicates the
position called point (q.v.) at which insertion and deletion takes
place.  The cursor is part of the terminal, and often blinks or
underlines the character where it is located.  @Note(IName="Cursor",
Node="Screen").

Customization @\Customization is making minor changes in the way EMACS
works.  It is often done by setting variables
(@Note(Node="Variables").) or by reconnecting commands
(@Note(IName="Reconnect", Name="Functions", Node="MMArcana").).

Defun @\A defun is a list at the top level of list structure in a Lisp
program.  It is so named because most such lists are calls to the Lisp
function defun.  @Note(Node="Defuns").

Delete @\This is the label used on some keyboards for the Rubout
character.

Deletion @\Deletion means erasing text without saving it.  EMACS
deletes text only when it is expected not to be worth saving (all
whitespace, or only one character).  The alternative is killing
(q.v.).  @Note(IName="Deletion", Node="Killing").

Dispatch Table @\The dispatch table is what records the connections
(q.v.) from command characters to functions.  Think of a telephone
switchboard connecting incoming lines (commands) to telephones
(functions).  A standard EMACS has one set of connections; a
customized EMACS may have different connections.
@Note(IName="Dispatch Table", Name="Functions", Node="MMArcana").

Echo Area @\The echo area is the bottom three lines of the screen, used
for echoing the arguments to commands, for asking questions, and
printing brief messages.  @Note(IName="Echo Area", Node="Screen").

Echoing @\Echoing is acknowledging the receipt of commands by
displaying them (in the echo area).  Most programs other than EMACS
echo all their commands.  EMACS never echoes single-character
commands; longer commands echo only if you pause while typing them.

Error Messages @\Error messages are single lines of output printed by
EMACS when the user or a TECO program asks for something impossible.
They appear at the top of the screen and end with a question mark.

Escape @\Escape is the label used on some keyboards for the Altmode
character.

Exiting @\Exiting EMACS means returning to EMACS's superior, normally
@ITS(HACTRN)@Twenex(EXEC).  @Note(Node="Exiting").  Exiting a
recursive editing level (q.v.) means allowing the command which
invoked the recursive editing to complete normally.  For example, if
you are editing a message to be sent, and you exit, the message is
sent.

Extended Command @\An extended command is a command which consists of
the character Meta-X followed by the command name (really, the name of
a function (q.v.)).  An extended command requires several characters of
input, but its name is made up of English words, so it is easy to
remember.  @Note(Name="Extended Commands", Node="M-X").

Extension @\Extension means making changes to EMACS which go beyond the
bounds of mere customization.  If customization is moving the
furniture around in a room, extension is building new furniture.
@Infonote(Name="Extension", File="CONV").

Filling @\Filling text means moving text from line to line so that all
the lines are approximately the same length.  @Note(Node="Filling").

Function @\A function is a named subroutine of EMACS.  When you type a
command, EMACS executes a function which corresponds to the command,
and the function does the work.  Character commands are connected to
functions through the dispatch table (q.v.).  Extended commands
contain the name of the function to be called; this allows you to call
any function.  @Note(IName="Functions", Name="Extended Commands", Node="M-X").

Global @\The global value of a variable or of a command character
definition applies to all buffers and all files (except those which
have their own local values of the variable or definition).
@Note(IName="Global", Node="Variables").

Grinding @\Grinding means reformatting a program so that it is indented
according to its structure.  @Note(Node="Grinding").

Help @\You can type the Help character at any time to ask what options
you have, or to ask what any command does.  @Note(Node="Help").

Home Directory @\Your home directory is the one on which your mail and
your init files are stored.  @Twenex{Twenex does not distinguish this
from the working directory (connected directory).}

INFO @\INFO is the subsystem for perusing tree-structured documentation
files.  The documentation in INFO includes a version of the EMACS
manual.

ITS @\ITS is the Incompatible Timesharing System written at the MIT 
Artificial Intelligence Lab.  EMACS was first developed on this
system.  Just what it is incompatible with has changed from year to
year.

Kill Ring @\The kill ring is where killed text is saved.  It holds the
last nine or so blocks of killed text.  It is called a ring because
you can bring any of the saved blocks to the front by rotating the ring.
@Note(IName="Kill ring", Node="Un-Killing").

Killing @\Killing means erasing text and saving it inside EMACS to be
recovered later if desired.  Most EMACS commands to erase text do
killing, as opposed to deletion (q.v.).  @Note(Node="Killing").

List @\A list is, approximately, a text string beginning with an open
parenthesis and ending with the matching close parenthesis.
@Note(Node="Lists").  Actually there are a few complications to the
syntax, which is controlled by the syntax table
(@Note(Node="Syntax").).

Local @\A local value of a variable or of a command character
definition applies to only one buffer or file.  @Note(Node="Locals").

Local Modes List @\A local modes list appears in a file to specify
local values for variables or command character definitions, to be in
effect while visiting that file.

M- @\M- in the name of a character is an abbreviation for Meta.

M-X @\M-X is the character which begins an extended command (q.v.).
Extended commands have come to be known also as "M-X commands", and an
individual extended command is often referred to as "M-X such-and such".
@Note(Node="M-X").

Major Mode @\The major modes are a mutually exclusive set of options
which configure EMACS for editing a certain sort of text.  Ideally,
each programming language has its own major mode.  @Note(Name="Major
Modes", Node="MajorModes").

Mark @\The mark points, invisibly, to a position in the text.  Many
commands operate on the text between point and the mark (known as the
region, q.v.).  @Note(Node="Mark").

Meta @\Meta refers to the Meta key.  A character's name
includes the word Meta if the Meta key must be held down in
order to type the character.  If there is no Meta key, then the
Altmode character is used as a prefix instead.  @Note(IName="Meta",
Node="Characters").

Meta Character @\A Meta character is one whose character code includes
the Meta bit.  These characters can be typed only by means of a Meta
key or by means of the metizer command (q.v.).

Metizer @\The metizer is another term for the bit prefix character for
the Meta bit; namely, Altmode (q.v.).

Minibuffer @\The minibuffer is a facility for editing and then
executing a TECO program.  @Note(Node="Minibuffer").

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 is both the name of an option (q.v.) and the name of an extended
command to set the option.  @Note(Name="Minor Modes", Node="MinorModes").

MM-command @\This is an obsolete synonym for "extended command".

Mode line @\The mode line is a line just above the echo area (q.v.),
used for status information.  @Note(Name="Mode Line",
Node="ModeLine").

Narrowing @\Narrowing means limiting editing 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.  @Note(Node="Narrowing").

Node @\The node is the unit of structure of INFO (q.v.) files.
@Manual{When
referring to documentation contained only in INFO files, we sometimes
refer to a node of a specific name, in a specific file, as in
"@INFONote(File="CONV", Node="Hooks", Name="Hooks")".}

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.  @Note(Name="Numeric Arguments",
Node="Arguments").

Option @\An option is a variable which exists to be set by the user to
change the behavior of EMACS commands.  This is an important method of
customization.  @Note(IName="Options", Node="Variables").

Parse @\We say that EMACS parses words or expressions in the text being
edited.  Really, all it knows how to do is find the other end of a
word or expression.  @Note(IName="Parse", Node="Syntax").

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.  @Note(IName="Point", Node="Basic").

Prefix Character @\A prefix character is a command whose sole function
is to introduce a set of multi-character commands.  Control-X (q.v.)@;
is a prefix character.  The bit prefix characters (q.v.) are other
examples.

Prompt @\A prompt is text printed in the echo area to ask the user for
input.  Printing a prompt is called "prompting".  EMACS can prompt
when a command requires an argument, or when only part of a command
has been typed.  However, the prompt will not appear unless you pause
in your typing.  @Note(IName="Prompt", Name="Extended Commands",
Node="M-X").

Q-Registers @\Q-registers are internal TECO variables which can be
used by EMACS or by the user to store text or numbers.
@INFO{@Note(Node="Copying",
IName="Q-Registers")}@Manual{@Note(Node="Q-Registers")}.

Quitting @\Quitting means interrupting a command which is partially
typed in or already executing.  It is done with Control-G.
@Note(Node="Quitting").

Quoting @\Quoting means depriving a character of its usual special
significance.  It is usually done with Control-Q.  What constitutes
special significance depends on the context and on convention.  For
example, an "ordinary" character as an EMACS command inserts itself;
so you can insert any other character, such as Rubout, by quoting it
as in Control-Q Rubout.  Not all contexts allow quoting.
@Note(Iname="Quoting", Name="Basic Editing", Node="Basic").

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 "]").
@Note(Name="Recursive Editing Level", Node="Recursive").

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.  @Note(IName="Redisplay", Node="Screen").

Region @\The region is the text between point (q.v.) and the mark
(q.v.).  The terminal's cursor indicates the location of point, but
the mark is invisible.  Many commands operate on the text of the
region.  @Note(IName="Region", Node="Mark").

Return @\Return is the carriage return character, used as input to
EMACS.  Return is used as a command in itself to insert a line
separator.  It also terminates arguments for most commands.
@Note(IName="Return", Node="Characters").

Rubout @\Rubout is a character, sometimes labelled "Delete".  It is
used as a command to delete one character of text.  It also deletes
one character when an EMACS command is reading an argument.

S-expression @\An s-expression is the basic syntactic unit of Lisp:
either a list, or a symbol containing no parentheses (actually, there
are a few exceptions to the rule, based on the syntax of Lisp).
@Note(IName="S-expressions", Node="Lists").

Selecting @\Selecting a buffer (q.v.) means making editing commands
apply to that buffer as opposed to any other.  At all times one buffer
is selected and editing takes place in that buffer.
@Note(IName="Select", Node="Buffers").

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.  @Note(IName="Self-documentation", Node="Help").

String Argument @\A string argument is an argument which follows the
command name in an extended command.  In "M-X Aproposword<cr>",
"Word" is a string argument to the Apropos command.
@Note(IName="String Arguments", Name="Extended Commands", Node="M-X").

Subsystem @\A subsystem of EMACS is an EMACS command which, itself,
reads commands and displays the results.  Examples are INFO, which is
for perusing documentation; DIRED, which is for editing directories;
@ITS[RMAIL and] BABYL, which @ITS{are}@Twenex{is} for reading and
editing mail.  The word "subsystem" implies that it offers many
independent commands which can be used freely.  If an EMACS function
asks specific questions, we do not call it a subsystem.

@\Usually the subsystem continues in operation until a specific command
to exit (usually "Q") is typed.  The commands for a subsystem do not
usually resemble ordinary EMACS commands, since editing text is not
their purpose.  The Help character should elicit the subsystem's
documentation.  @Note(Node="Subsystems").

Syntax Table @\The syntax table tells EMACS which characters are part
of a word, which characters balance each other like parentheses, etc.
@Note(Node="Syntax").

Tailoring @\This is a synonym for customization (q.v.).

TECO Search String @\A TECO search string is a sort of pattern used by
the TECO search command, and also by various EMACS commands which use
the TECO search command.  @Note(Name="TECO search strings",
Node="TECOsearch").

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 or a subsystem
(q.v.).

Twenex @\Twenex is the operating system which DEC likes to call
"TOPS-20".  However, a person should not be forced to call a system
"tops" unless he really thinks so.  Come now, DEC, don't you think
people will praise your products voluntarily?  The name "Twenex" is
also more appropriate because Twenex was developed from the Tenex
system, and has no relationship to "TOPS-10".  What's more, it's very
euphonious.

Typeout @\Typeout is a message, printed by an EMACS command, which
overwrites the area normally used for displaying the text being
edited, but which does not become part of the text.  Typeout is used
for messages which might be too long to fit in the echo area (q.v.).
@Note(IName="Typeout", Node="Screen").

Undo @\Undo is a command which undoes the effect on the buffer of a
previous command.  Only some commands are undoable and only the
most recent undoable command can be undone.  @Note(Node="Undo").

Un-killing @\Un-killing means reinserting text previously killed.  It
can be used to undo a mistaken kill, or for copying or moving text.
@Note(Node="Un-killing").

User Name @\Your user name is the name you use to log in.  It
identifies you as opposed to all the other users.  It may be the same
as your home directory's name.

Variable @\A variable is a name with which EMACS associates a value,
which can be a number or a string.  @Note(Node="Variables").  Some
variables ("options") are intended to be used or set by the user;
others are for purely internal purposes.

Virtual Boundaries@ @ @ @\The virtual boundaries delimit the accessible part
of the buffer, when narrowing (q.v.) is in effect.
@Note(IName="Virtual Boundaries", Node="Narrowing").

Visiting @\Visiting a file means loading its contents into a buffer
(q.v.) where they can be edited.  @Note(Node="Visiting").

Wall Chart @\The wall chart is a very brief EMACS reference sheet
giving one line of information about each short command.
@Case(Device, Dover "A copy of the wall chart appears in this manual.
")

Whitespace @\Whitespace is any run of consecutive formatting characters
(space, tab, carriage return, linefeed, and backspace).

Widening @\Widening is the operation which undoes narrowing (q.v.).
@Note(IName="Widening", Node="Narrowing").

Window @\A window is a region of the screen in which text being edited
is displayed.  EMACS can divide the screen into two windows.
@Note(Node="Windows").  "The window" also means the position in the
buffer which is at the top of the screen.  @Note(IName="The Window",
Node="Display").

@ITS{ Working Directory @\This is the directory which you have told
the system you wish to operate on primarily at the moment.  This is
usually the same as your home directory (q.v.).  It is specified with
the DDT command :CWD <directory>.}

@Twenex{
Working Directory @\This is another term for the directory you are
connected to, a term which is used on other systems besides Twenex.}

Yanking @\This is a synonym for un-killing (q.v.).

^R @\The string "^R" is the beginning of many function names.
@Note(IName="^R", Name="Functions", Node="MMArcana").

^R Mode @\^R mode is the real time editing mode of TECO.  EMACS
@xxi[always] operates in this mode.

@End(Description)