<s>
Emacs	B-Application
,	O
originally	O
named	O
EMACS	B-Application
(	O
an	O
acronym	O
for	O
"	O
Editor	B-Application
MACroS	I-Application
"	O
)	O
,	O
is	O
a	O
family	O
of	O
text	B-Application
editors	I-Application
that	O
are	O
characterized	O
by	O
their	O
extensibility	B-Architecture
.	O
</s>
<s>
The	O
manual	O
for	O
the	O
most	O
widely	O
used	O
variant	O
,	O
GNU	B-Application
Emacs	I-Application
,	O
describes	O
it	O
as	O
"	O
the	O
extensible	B-Architecture
,	O
customizable	O
,	O
self-documenting	O
,	O
real-time	O
display	O
editor	O
"	O
.	O
</s>
<s>
Development	O
of	O
the	O
first	O
Emacs	B-Application
began	O
in	O
the	O
mid-1970s	O
,	O
and	O
work	O
on	O
its	O
direct	O
descendant	O
,	O
GNU	B-Application
Emacs	I-Application
,	O
continues	O
actively	O
;	O
the	O
latest	O
version	O
is	O
28.2	O
,	O
released	O
in	O
September	O
2022	O
.	O
</s>
<s>
Emacs	B-Application
has	O
over	O
10,000	O
built-in	O
commands	O
and	O
its	O
user	B-Application
interface	I-Application
allows	O
the	O
user	O
to	O
combine	O
these	O
commands	O
into	O
macros	O
to	O
automate	O
work	O
.	O
</s>
<s>
Implementations	O
of	O
Emacs	B-Application
typically	O
feature	O
a	O
dialect	O
of	O
the	O
Lisp	B-Language
programming	I-Language
language	I-Language
,	O
allowing	O
users	O
and	O
developers	O
to	O
write	O
new	O
commands	O
and	O
applications	O
for	O
the	O
editor	O
.	O
</s>
<s>
Extensions	O
have	O
been	O
written	O
to	O
,	O
among	O
other	O
things	O
,	O
manage	O
files	B-Operating_System
,	O
remote	B-Protocol
access	I-Protocol
,	O
e-mail	B-Operating_System
,	O
outlines	B-Operating_System
,	O
multimedia	O
,	O
git	B-Application
integration	O
,	O
and	O
RSS	O
feeds	O
,	O
as	O
well	O
as	O
implementations	O
of	O
ELIZA	B-Application
,	O
Pong	B-Application
,	O
Conway	O
's	O
Life	O
,	O
Snake	B-Application
,	O
Dunnet	B-Operating_System
,	O
and	O
Tetris	B-Device
.	O
</s>
<s>
The	O
original	O
EMACS	B-Application
was	O
written	O
in	O
1976	O
by	O
David	O
A	O
.	O
</s>
<s>
Moon	O
and	O
Guy	O
L	O
.	O
Steele	O
Jr.	O
as	O
a	O
set	O
of	O
Editor	B-Application
MACroS	I-Application
for	O
the	O
TECO	B-Application
editor	O
.	O
</s>
<s>
It	O
was	O
inspired	O
by	O
the	O
ideas	O
of	O
the	O
TECO-macro	O
editors	O
TECMAC	O
and	O
TMACS	O
.	O
</s>
<s>
The	O
most	O
popular	O
,	O
and	O
most	O
ported	O
,	O
version	O
of	O
Emacs	B-Application
is	O
GNU	B-Application
Emacs	I-Application
,	O
which	O
was	O
created	O
by	O
Richard	O
Stallman	O
for	O
the	B-Application
GNU	I-Application
Project	I-Application
.	O
</s>
<s>
XEmacs	B-Language
is	O
a	O
variant	O
that	O
branched	B-Application
from	O
GNU	B-Application
Emacs	I-Application
in	O
1991	O
.	O
</s>
<s>
GNU	B-Application
Emacs	I-Application
and	O
XEmacs	B-Language
use	O
similar	O
Lisp	B-Language
dialects	O
and	O
are	O
,	O
for	O
the	O
most	O
part	O
,	O
compatible	O
with	O
each	O
other	O
.	O
</s>
<s>
XEmacs	B-Language
development	O
is	O
inactive	O
.	O
</s>
<s>
Emacs	B-Application
is	O
,	O
along	O
with	O
vi	B-Application
,	O
one	O
of	O
the	O
two	O
main	O
contenders	O
in	O
the	O
traditional	O
editor	B-Language
wars	I-Language
of	O
Unix	B-Application
culture	O
.	O
</s>
<s>
Emacs	B-Application
is	O
among	O
the	O
oldest	O
free	B-License
and	I-License
open	I-License
source	I-License
projects	O
still	O
under	O
development	O
.	O
</s>
<s>
Emacs	B-Application
development	O
began	O
during	O
the	O
1970s	O
at	O
the	O
MIT	O
AI	O
Lab	O
,	O
whose	O
PDP-6	B-Device
and	O
PDP-10	B-Device
computers	O
used	O
the	O
Incompatible	B-Application
Timesharing	I-Application
System	I-Application
(	O
ITS	O
)	O
operating	B-General_Concept
system	I-General_Concept
that	O
featured	O
a	O
default	O
line	B-Application
editor	I-Application
known	O
as	O
Tape	B-Application
Editor	I-Application
and	I-Application
Corrector	I-Application
(	O
TECO	B-Application
)	O
.	O
</s>
<s>
Unlike	O
most	O
modern	O
text	B-Application
editors	I-Application
,	O
TECO	B-Application
used	O
separate	O
modes	O
in	O
which	O
the	O
user	O
would	O
either	O
add	O
text	O
,	O
edit	O
existing	O
text	O
,	O
or	O
display	O
the	O
document	O
.	O
</s>
<s>
One	O
could	O
not	O
place	O
characters	O
directly	O
into	O
a	O
document	O
by	O
typing	O
them	O
into	O
TECO	B-Application
,	O
but	O
would	O
instead	O
enter	O
a	O
character	O
( 	O
 '	O
i	O
 '	O
)	O
in	O
the	O
TECO	B-Application
command	O
language	O
telling	O
it	O
to	O
switch	O
to	O
input	O
mode	O
,	O
enter	O
the	O
required	O
characters	O
,	O
during	O
which	O
time	O
the	O
edited	O
text	O
was	O
not	O
displayed	O
on	O
the	O
screen	O
,	O
and	O
finally	O
enter	O
a	O
character	O
(	O
<esc>	O
)	O
to	O
switch	O
the	O
editor	O
back	O
to	O
command	O
mode	O
.	O
</s>
<s>
This	O
behavior	O
is	O
similar	O
to	O
that	O
of	O
the	O
program	O
ed	B-Application
.	O
</s>
<s>
By	O
the	O
1970s	O
,	O
TECO	B-Application
was	O
already	O
an	O
old	O
program	O
,	O
initially	O
released	O
in	O
1962	O
.	O
</s>
<s>
He	O
was	O
impressed	O
by	O
the	O
editor	O
's	O
intuitive	O
WYSIWYG	B-Application
(	O
What	B-Application
You	I-Application
See	I-Application
Is	I-Application
What	I-Application
You	I-Application
Get	I-Application
)	O
behavior	O
,	O
which	O
has	O
since	O
become	O
the	O
default	O
behavior	O
of	O
most	O
modern	O
text	B-Application
editors	I-Application
.	O
</s>
<s>
He	O
returned	O
to	O
MIT	O
where	O
Carl	O
Mikkelsen	O
,	O
a	O
hacker	O
at	O
the	O
AI	O
Lab	O
,	O
had	O
added	O
to	O
TECO	B-Application
a	O
combined	O
display/editing	O
mode	O
called	O
Control-R	O
that	O
allowed	O
the	O
screen	O
display	O
to	O
be	O
updated	O
each	O
time	O
the	O
user	O
entered	O
a	O
keystroke	O
.	O
</s>
<s>
Stallman	O
reimplemented	O
this	O
mode	O
to	O
run	O
efficiently	O
and	O
then	O
added	O
a	O
macro	O
feature	O
to	O
the	O
TECO	B-Application
display-editing	O
mode	O
that	O
allowed	O
the	O
user	O
to	O
redefine	O
any	O
keystroke	O
to	O
run	O
a	O
TECO	B-Application
program	O
.	O
</s>
<s>
E	O
had	O
another	O
feature	O
that	O
TECO	B-Application
lacked	O
:	O
random-access	O
editing	O
.	O
</s>
<s>
TECO	B-Application
was	O
a	O
page-sequential	O
editor	O
that	O
was	O
designed	O
for	O
editing	O
paper	O
tape	O
on	O
the	O
PDP-1	B-Device
at	O
a	O
time	O
when	O
computer	O
memory	O
was	O
generally	O
small	O
due	O
to	O
cost	O
,	O
and	O
it	O
was	O
a	O
feature	O
of	O
TECO	B-Application
that	O
allowed	O
editing	O
on	O
only	O
one	O
page	O
at	O
a	O
time	O
sequentially	O
in	O
the	O
order	O
of	O
the	O
pages	O
in	O
the	O
file	O
.	O
</s>
<s>
Instead	O
of	O
adopting	O
E	O
's	O
approach	O
of	O
structuring	O
the	O
file	O
for	O
page-random	O
access	O
on	O
disk	O
,	O
Stallman	O
modified	O
TECO	B-Application
to	O
handle	O
large	O
buffers	B-General_Concept
more	O
efficiently	O
and	O
changed	O
its	O
file-management	O
method	O
to	O
read	O
,	O
edit	O
,	O
and	O
write	O
the	O
entire	O
file	O
as	O
a	O
single	O
buffer	B-General_Concept
.	O
</s>
<s>
The	O
new	O
version	O
of	O
TECO	B-Application
quickly	O
became	O
popular	O
at	O
the	O
AI	O
Lab	O
and	O
soon	O
accumulated	O
a	O
large	O
collection	O
of	O
custom	O
macros	O
whose	O
names	O
often	O
ended	O
in	O
MAC	O
or	O
MACS	O
,	O
which	O
stood	O
for	O
macro	O
.	O
</s>
<s>
The	O
resulting	O
system	O
was	O
called	O
EMACS	B-Application
,	O
which	O
stood	O
for	O
Editing	O
MACroS	O
or	O
,	O
alternatively	O
,	O
E	O
with	O
MACroS	O
.	O
</s>
<s>
Stallman	O
picked	O
the	O
name	O
Emacs	B-Application
"	O
because	O
<E>	O
was	O
not	O
in	O
use	O
as	O
an	O
abbreviation	O
on	O
ITS	O
at	O
the	O
time.	O
"	O
</s>
<s>
The	O
first	O
operational	O
EMACS	B-Application
system	O
existed	O
in	O
late	O
1976	O
.	O
</s>
<s>
The	O
original	O
Emacs	B-Application
,	O
like	O
TECO	B-Application
,	O
ran	O
only	O
on	O
the	O
PDP-10	B-Device
running	O
ITS	O
.	O
</s>
<s>
Its	O
behavior	O
was	O
sufficiently	O
different	O
from	O
that	O
of	O
TECO	B-Application
that	O
it	O
could	O
be	O
considered	O
a	O
text	B-Application
editor	I-Application
in	O
its	O
own	O
right	O
,	O
and	O
it	O
quickly	O
became	O
the	O
standard	O
editing	O
program	O
on	O
ITS	O
.	O
</s>
<s>
Mike	O
McMahon	O
ported	O
Emacs	B-Application
from	O
ITS	O
to	O
the	O
TENEX	B-Operating_System
and	O
TOPS-20	B-Operating_System
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
Other	O
contributors	O
to	O
early	O
versions	O
of	O
Emacs	B-Application
include	O
Kent	O
Pitman	O
,	O
Earl	O
Killian	O
,	O
and	O
Eugene	O
Ciccarelli	O
.	O
</s>
<s>
By	O
1979	O
,	O
Emacs	B-Application
was	O
the	O
main	O
editor	O
used	O
in	O
MIT	O
's	O
AI	O
lab	O
and	O
its	O
Laboratory	O
for	O
Computer	O
Science	O
.	O
</s>
<s>
In	O
the	O
following	O
years	O
,	O
programmers	O
wrote	O
a	O
variety	O
of	O
Emacs-like	O
editors	O
for	O
other	O
computer	O
systems	O
.	O
</s>
<s>
These	O
included	O
EINE	B-Operating_System
(	O
EINE	B-Operating_System
Is	O
Not	O
EMACS	B-Application
)	O
and	O
ZWEI	B-Operating_System
(	O
ZWEI	B-Operating_System
Was	O
EINE	B-Operating_System
Initially	O
)	O
,	O
which	O
were	O
written	O
for	O
the	O
Lisp	B-Operating_System
machine	I-Operating_System
by	O
Mike	O
McMahon	O
and	O
Daniel	O
Weinreb	O
,	O
and	O
Sine	O
(	O
Sine	O
Is	O
Not	O
Eine	B-Operating_System
)	O
,	O
which	O
was	O
written	O
by	O
Owen	O
Theodore	O
Anderson	O
.	O
</s>
<s>
Weinreb	O
's	O
EINE	B-Operating_System
was	O
the	O
first	O
Emacs	B-Application
written	O
in	O
Lisp	B-Language
.	O
</s>
<s>
In	O
1978	O
,	O
Bernard	O
Greenberg	O
wrote	O
Multics	B-Operating_System
Emacs	I-Operating_System
almost	O
entirely	O
in	O
Multics	O
Lisp	B-Language
at	O
Honeywell	O
's	O
Cambridge	O
Information	O
Systems	O
Lab	O
.	O
</s>
<s>
Multics	B-Operating_System
Emacs	I-Operating_System
was	O
later	O
maintained	O
by	O
Richard	O
Soley	O
,	O
who	O
went	O
on	O
to	O
develop	O
the	O
NILE	O
Emacs-like	O
editor	O
for	O
the	O
NIL	O
Project	O
,	O
and	O
by	O
Barry	O
Margolin	O
.	O
</s>
<s>
Many	O
versions	O
of	O
Emacs	B-Application
,	O
including	O
GNU	B-Application
Emacs	I-Application
,	O
would	O
later	O
adopt	O
Lisp	B-Language
as	O
an	O
extension	B-Language
language	I-Language
.	O
</s>
<s>
James	O
Gosling	O
,	O
who	O
would	O
later	O
invent	O
NeWS	O
and	O
the	O
Java	B-Language
programming	I-Language
language	I-Language
,	O
wrote	O
Gosling	B-Operating_System
Emacs	I-Operating_System
in	O
1981	O
.	O
</s>
<s>
The	O
first	O
Emacs-like	O
editor	O
to	O
run	O
on	O
Unix	B-Application
,	O
Gosling	B-Operating_System
Emacs	I-Operating_System
was	O
written	O
in	O
C	B-Language
and	O
used	O
Mocklisp	B-Language
,	O
a	O
language	O
with	O
Lisp-like	O
syntax	O
,	O
as	O
an	O
extension	B-Language
language	I-Language
.	O
</s>
<s>
Early	O
Ads	O
for	O
Computer	O
Corporation	O
of	O
America	O
's	O
CCA	O
EMACS	B-Application
(	O
Steve	O
Zimmerman	O
)	O
.	O
</s>
<s>
1985	O
comparisons	O
to	O
GNU	B-Application
Emacs	I-Application
,	O
when	O
it	O
came	O
out	O
,	O
mentioned	O
free	B-Application
vs.	O
$	O
2,400	O
.	O
</s>
<s>
Richard	O
Stallman	O
began	O
work	O
on	O
GNU	B-Application
Emacs	I-Application
in	O
1984	O
to	O
produce	O
a	O
free	B-Application
software	I-Application
alternative	O
to	O
the	O
proprietary	B-Application
Gosling	B-Operating_System
Emacs	I-Operating_System
.	O
</s>
<s>
GNU	B-Application
Emacs	I-Application
was	O
initially	O
based	O
on	O
Gosling	B-Operating_System
Emacs	I-Operating_System
,	O
but	O
Stallman	O
's	O
replacement	O
of	O
its	O
Mocklisp	B-Language
interpreter	O
with	O
a	O
true	O
Lisp	B-Language
interpreter	O
required	O
that	O
nearly	O
all	O
of	O
its	O
code	O
be	O
rewritten	O
.	O
</s>
<s>
This	O
became	O
the	O
first	O
program	O
released	O
by	O
the	O
nascent	O
GNU	B-Application
Project	I-Application
.	O
</s>
<s>
GNU	B-Application
Emacs	I-Application
is	O
written	O
in	O
C	B-Language
and	O
provides	O
Emacs	B-Operating_System
Lisp	I-Operating_System
,	O
also	O
implemented	O
in	O
C	B-Language
,	O
as	O
an	O
extension	B-Language
language	I-Language
.	O
</s>
<s>
The	O
first	O
widely	O
distributed	O
version	O
of	O
GNU	B-Application
Emacs	I-Application
was	O
version	O
15.34	O
,	O
released	O
later	O
in	O
1985	O
.	O
</s>
<s>
Early	O
versions	O
of	O
GNU	B-Application
Emacs	I-Application
were	O
numbered	O
as	O
1.x.x	O
,	O
with	O
the	O
initial	O
digit	O
denoting	O
the	O
version	O
of	O
the	O
C	B-Language
core	O
.	O
</s>
<s>
In	O
September	O
2014	O
,	O
it	O
was	O
announced	O
on	O
the	O
GNU	O
emacs-devel	O
mailing	O
list	O
that	O
GNU	B-Application
Emacs	I-Application
would	O
adopt	O
a	O
rapid	O
release	O
strategy	O
and	O
version	O
numbers	O
would	O
increment	O
more	O
quickly	O
in	O
the	O
future	O
.	O
</s>
<s>
GNU	B-Application
Emacs	I-Application
offered	O
more	O
features	O
than	O
Gosling	B-Operating_System
Emacs	I-Operating_System
,	O
in	O
particular	O
a	O
full-featured	O
Lisp	B-Language
as	O
its	O
extension	B-Language
language	I-Language
,	O
and	O
soon	O
replaced	O
Gosling	B-Operating_System
Emacs	I-Operating_System
as	O
the	O
de	O
facto	O
Unix	B-Application
Emacs	B-Application
editor	O
.	O
</s>
<s>
Markus	O
Hess	O
exploited	O
a	O
security	O
flaw	O
in	O
GNU	B-Application
Emacs	I-Application
 '	O
email	O
subsystem	O
in	O
his	O
1986	O
cracking	O
spree	O
in	O
which	O
he	O
gained	O
superuser	B-Application
access	O
to	O
Unix	B-Application
computers	O
.	O
</s>
<s>
Most	O
of	O
GNU	B-Application
Emacs	I-Application
functionality	O
is	O
implemented	O
through	O
a	O
scripting	B-Language
language	I-Language
called	O
Emacs	B-Operating_System
Lisp	I-Operating_System
.	O
</s>
<s>
Because	O
about	O
70%	O
of	O
GNU	B-Application
Emacs	I-Application
is	O
written	O
in	O
the	O
Emacs	B-Operating_System
Lisp	I-Operating_System
extension	B-Language
language	I-Language
,	O
one	O
only	O
needs	O
to	O
port	O
the	O
C	B-Language
core	O
which	O
implements	O
the	O
Emacs	B-Operating_System
Lisp	I-Operating_System
interpreter	O
.	O
</s>
<s>
This	O
makes	O
porting	O
Emacs	B-Application
to	O
a	O
new	O
platform	O
considerably	O
less	O
difficult	O
than	O
porting	O
an	O
equivalent	O
project	O
consisting	O
of	O
native	B-Language
code	I-Language
only	O
.	O
</s>
<s>
GNU	B-Application
Emacs	I-Application
development	O
was	O
relatively	O
closed	O
until	O
1999	O
and	O
was	O
used	O
as	O
an	O
example	O
of	O
the	O
Cathedral	O
development	O
style	O
in	O
The	O
Cathedral	O
and	O
the	O
Bazaar	O
.	O
</s>
<s>
The	O
project	O
has	O
since	O
adopted	O
a	O
public	O
development	O
mailing	O
list	O
and	O
anonymous	O
CVS	B-Application
access	O
.	O
</s>
<s>
Development	O
took	O
place	O
in	O
a	O
single	O
CVS	B-Application
trunk	O
until	O
2008	O
and	O
was	O
then	O
switched	O
to	O
the	O
Bazaar	O
DVCS	B-Protocol
.	O
</s>
<s>
On	O
November	O
11	O
,	O
2014	O
,	O
development	O
was	O
moved	O
to	O
Git	B-Application
.	O
</s>
<s>
Richard	O
Stallman	O
has	O
remained	O
the	O
principal	O
maintainer	O
of	O
GNU	B-Application
Emacs	I-Application
,	O
but	O
he	O
has	O
stepped	O
back	O
from	O
the	O
role	O
at	O
times	O
.	O
</s>
<s>
As	O
of	O
early	O
2014	O
,	O
GNU	B-Application
Emacs	I-Application
has	O
had	O
579	O
individual	O
committers	B-Protocol
throughout	O
its	O
history	O
.	O
</s>
<s>
Lucid	B-Language
Emacs	I-Language
,	O
based	O
on	O
an	O
early	O
alpha	O
version	O
of	O
GNU	B-Application
Emacs	I-Application
19	O
,	O
was	O
developed	O
beginning	O
in	O
1991	O
by	O
Jamie	B-Operating_System
Zawinski	I-Operating_System
and	O
others	O
at	O
Lucid	O
Inc	O
.	O
One	O
of	O
the	O
best-known	O
early	O
forks	B-Application
in	O
free	B-Application
software	I-Application
development	I-Application
occurred	O
when	O
the	O
codebases	O
of	O
the	O
two	O
Emacs	B-Application
versions	O
diverged	O
and	O
the	O
separate	O
development	O
teams	O
ceased	O
efforts	O
to	O
merge	O
them	O
back	O
into	O
a	O
single	O
program	O
.	O
</s>
<s>
Lucid	B-Language
Emacs	I-Language
has	O
since	O
been	O
renamed	O
XEmacs	B-Language
.	O
</s>
<s>
Its	O
development	O
is	O
currently	O
inactive	O
,	O
with	O
the	O
most	O
recent	O
stable	O
version	O
21.4.22	O
released	O
in	O
January	O
2009	O
(	O
while	O
a	O
beta	O
was	O
released	O
in	O
2013	O
)	O
,	O
while	O
GNU	B-Application
Emacs	I-Application
has	O
implemented	O
many	O
formerly	O
XEmacs-only	O
features	O
.	O
</s>
<s>
Other	O
notable	O
forks	B-Application
include	O
:	O
</s>
<s>
In	O
the	O
past	O
,	O
projects	O
aimed	O
at	O
producing	O
small	O
versions	O
of	O
Emacs	B-Application
proliferated	O
.	O
</s>
<s>
GNU	B-Application
Emacs	I-Application
was	O
initially	O
targeted	O
at	O
computers	O
with	O
a	O
32-bit	O
flat	O
address	O
space	O
and	O
at	O
least	O
1MiB	O
of	O
RAM	O
.	O
</s>
<s>
Such	O
computers	O
were	O
high	O
end	O
workstations	B-Device
and	O
minicomputers	B-Architecture
in	O
the	O
1980s	O
,	O
and	O
this	O
left	O
a	O
need	O
for	O
smaller	O
reimplementations	O
that	O
would	O
run	O
on	O
common	O
personal	B-Device
computer	I-Device
hardware	O
.	O
</s>
<s>
Other	O
projects	O
aim	O
to	O
implement	O
Emacs	B-Application
in	O
a	O
different	O
dialect	O
of	O
Lisp	B-Language
or	O
a	O
different	O
programming	O
language	O
altogether	O
.	O
</s>
<s>
MicroEMACS	B-Language
,	O
which	O
was	O
originally	O
written	O
by	O
Dave	O
Conroy	O
and	O
further	O
developed	O
by	O
Daniel	O
Lawrence	O
and	O
which	O
exists	O
in	O
many	O
variations	O
.	O
</s>
<s>
mg	B-Application
,	O
originally	O
called	O
MicroGNUEmacs	B-Application
and	O
,	O
later	O
,	O
mg2a	O
,	O
a	O
public-domain	O
offshoot	O
of	O
MicroEMACS	B-Language
intended	O
to	O
more	O
closely	O
resemble	O
GNU	B-Application
Emacs	I-Application
.	O
</s>
<s>
Now	O
installed	O
by	O
default	O
on	O
OpenBSD	B-Operating_System
.	O
</s>
<s>
JOVE	B-Application
(	O
Jonathan	O
's	O
Own	O
Version	O
of	O
Emacs	B-Application
)	O
,	O
Jonathan	B-Application
Payne	I-Application
's	O
non-programmable	O
Emacs	B-Application
implementation	O
for	O
UNIX-like	B-Operating_System
systems	I-Operating_System
.	O
</s>
<s>
MINCE	B-Operating_System
(	O
MINCE	B-Operating_System
Is	O
Not	O
Complete	O
Emacs	B-Application
)	O
,	O
a	O
version	O
for	O
CP/M	B-Application
and	O
later	O
DOS	B-Device
,	O
from	O
Mark	O
of	O
the	O
Unicorn	O
.	O
</s>
<s>
MINCE	B-Operating_System
evolved	O
into	O
Final	O
Word	O
,	O
which	O
eventually	O
became	O
the	O
Borland	O
Sprint	B-Application
word	B-General_Concept
processor	I-General_Concept
.	O
</s>
<s>
Perfect	B-Operating_System
Writer	I-Operating_System
,	O
a	O
CP/M	B-Application
implementation	O
derived	O
from	O
MINCE	B-Operating_System
that	O
was	O
included	O
circa	O
1982	O
as	O
the	O
default	O
word	B-General_Concept
processor	I-General_Concept
with	O
the	O
very	O
earliest	O
releases	O
of	O
the	O
Kaypro	O
II	O
and	O
Kaypro	O
IV	O
.	O
</s>
<s>
It	O
was	O
later	O
provided	O
with	O
the	O
Kaypro	O
10	O
as	O
an	O
alternative	O
to	O
WordStar	B-Application
.	O
</s>
<s>
Freemacs	B-Application
,	O
a	O
DOS	B-Device
version	O
that	O
uses	O
an	O
extension	B-Language
language	I-Language
based	O
on	O
text	O
macro	O
expansion	O
and	O
fits	O
within	O
the	O
original	O
64	O
KiB	O
flat	O
memory	O
limit	O
.	O
</s>
<s>
Zmacs	B-Operating_System
,	O
for	O
the	O
MIT	O
Lisp	B-Operating_System
Machine	I-Operating_System
and	O
its	O
descendants	O
,	O
implemented	O
in	O
ZetaLisp	B-Language
.	O
</s>
<s>
Epsilon	B-Operating_System
,	O
an	O
Emacs	B-Application
clone	O
by	O
Lugaru	O
Software	O
.	O
</s>
<s>
Versions	O
for	O
DOS	B-Device
,	O
Windows	O
,	O
Linux	B-Application
,	O
FreeBSD	O
,	O
Mac	O
OS	B-General_Concept
X	O
and	O
OS/2	O
are	O
bundled	O
in	O
the	O
release	O
.	O
</s>
<s>
It	O
uses	O
a	O
non-Lisp	O
extension	B-Language
language	I-Language
with	O
C	B-Language
syntax	O
and	O
used	O
a	O
very	O
early	O
concurrent	O
command	O
shell	O
buffer	B-General_Concept
implementation	O
under	O
the	O
single-tasking	O
MS-DOS	O
.	O
</s>
<s>
PceEmacs	O
is	O
the	O
Emacs-based	O
editor	O
for	O
SWI-Prolog	B-Application
.	O
</s>
<s>
Hemlock	B-Application
,	O
originally	O
written	O
in	O
Spice	B-Language
Lisp	I-Language
,	O
then	O
Common	B-Language
Lisp	I-Language
.	O
</s>
<s>
A	O
part	O
of	O
CMU	B-Language
Common	I-Language
Lisp	I-Language
.	O
</s>
<s>
Influenced	O
by	O
Zmacs	B-Operating_System
.	O
</s>
<s>
Later	O
forked	O
by	O
Lucid	B-Language
Common	I-Language
Lisp	I-Language
(	O
as	O
Helix	O
)	O
,	O
LispWorks	B-Language
and	O
Clozure	B-Application
CL	I-Application
projects	O
.	O
</s>
<s>
There	O
is	O
also	O
a	O
Portable	O
Hemlock	B-Application
project	O
,	O
which	O
aims	O
to	O
provide	O
a	O
Hemlock	B-Application
,	O
which	O
runs	O
on	O
several	O
Common	B-Language
Lisp	I-Language
implementations	O
.	O
</s>
<s>
edwin	B-Application
,	O
an	O
Emacs-like	O
text	B-Application
editor	I-Application
included	O
with	O
MIT/GNU	B-Application
Scheme	I-Application
.	O
</s>
<s>
The	O
Cocoa	B-Application
text	I-Application
system	I-Application
uses	O
some	O
of	O
the	O
same	O
terminology	O
and	O
understands	O
many	O
Emacs	B-Application
navigation	O
bindings	O
.	O
</s>
<s>
This	O
is	O
possible	O
because	O
the	O
native	O
UI	O
uses	O
the	O
Command	B-Device
key	I-Device
(	O
equivalent	O
to	O
Super	O
)	O
instead	O
of	O
the	O
Control	B-Device
key	I-Device
.	O
</s>
<s>
Eclipse	B-Application
(	O
IDE	O
)	O
provides	O
a	O
set	O
of	O
Emacs	B-Application
keybindings	O
.	O
</s>
<s>
Epsilon	B-Operating_System
(	O
text	B-Application
editor	I-Application
)	O
Defaults	O
to	O
Emacs	B-Application
emulation	O
and	O
supports	O
a	O
vi	B-Application
mode	O
.	O
</s>
<s>
GNOME	B-Language
Builder	I-Language
has	O
an	O
emulation	O
mode	O
for	O
Emacs	B-Application
.	O
</s>
<s>
GNU	B-Application
Readline	I-Application
is	O
a	O
line	B-Application
editor	I-Application
that	O
understands	O
the	O
standard	O
Emacs	B-Application
navigation	O
keybindings	O
.	O
</s>
<s>
It	O
also	O
has	O
a	O
vi	B-Application
emulation	O
mode	O
.	O
</s>
<s>
IntelliJ	B-Language
IDEA	I-Language
provides	O
a	O
set	O
of	O
Emacs	B-Application
keybindings	O
.	O
</s>
<s>
JED	B-Application
has	O
an	O
emulation	O
mode	O
for	O
Emacs	B-Application
.	O
</s>
<s>
Joe	B-Device
's	I-Device
Own	I-Device
Editor	I-Device
emulates	O
Emacs	B-Application
keybindings	O
when	O
invoked	O
as	O
.	O
</s>
<s>
MATLAB	B-Language
provides	O
Emacs	B-Application
keybindings	O
for	O
its	O
editor	O
.	O
</s>
<s>
KornShell	B-Language
has	O
an	O
Emacs	B-Application
line	O
editing	O
mode	O
that	O
predates	O
Gnu	B-Application
Readline	I-Application
.	O
</s>
<s>
Visual	B-Language
Studio	I-Language
Code	I-Language
provides	O
an	O
to	O
emulate	O
Emacs	B-Application
keybindings	O
.	O
</s>
<s>
Oracle	B-Operating_System
SQL	I-Operating_System
Developer	I-Operating_System
can	O
save	O
and	O
load	O
alternative	O
keyboard-shortcut	O
layouts	O
.	O
</s>
<s>
One	O
of	O
the	O
built-in	O
layouts	O
provides	O
Emacs-like	O
keybindings	O
,	O
including	O
using	O
different	O
commands	O
to	O
achieve	O
closer	O
behavior	O
.	O
</s>
<s>
Emacs	B-Application
is	O
primarily	O
a	O
text	B-Application
editor	I-Application
and	O
is	O
designed	O
for	O
manipulating	O
pieces	O
of	O
text	O
,	O
although	O
it	O
is	O
capable	O
of	O
formatting	O
and	O
printing	O
documents	O
like	O
a	O
word	B-General_Concept
processor	I-General_Concept
by	O
interfacing	O
with	O
external	O
programs	O
such	O
as	O
LaTeX	B-Application
,	O
Ghostscript	B-Language
or	O
a	O
web	O
browser	O
.	O
</s>
<s>
Emacs	B-Application
provides	O
commands	O
to	O
manipulate	O
and	O
differentially	O
display	O
semantic	O
units	O
of	O
text	O
such	O
as	O
words	O
,	O
sentences	O
,	O
paragraphs	O
and	O
source	O
code	O
constructs	O
such	O
as	O
functions	O
.	O
</s>
<s>
GNU	B-Application
Emacs	I-Application
is	O
a	O
real-time	O
display	O
editor	O
,	O
as	O
its	O
edits	O
are	O
displayed	O
onscreen	O
as	O
they	O
occur	O
.	O
</s>
<s>
This	O
is	O
standard	O
behavior	O
for	O
modern	O
text	B-Application
editors	I-Application
but	O
EMACS	B-Application
was	O
among	O
the	O
earliest	O
to	O
implement	O
this	O
.	O
</s>
<s>
This	O
is	O
done	O
in	O
line	B-Application
editors	I-Application
,	O
such	O
as	O
ed	B-Application
(	O
unix	B-Application
)	O
,	O
ED	B-Application
(	O
CP/M	B-Application
)	O
,	O
and	O
Edlin	B-Application
(	O
MS-DOS	O
)	O
.	O
</s>
<s>
Almost	O
all	O
of	O
the	O
functionality	O
in	O
Emacs	B-Application
,	O
including	O
basic	O
editing	O
operations	O
such	O
as	O
the	O
insertion	O
of	O
characters	O
into	O
a	O
file	O
,	O
is	O
achieved	O
through	O
functions	O
written	O
in	O
a	O
dialect	O
of	O
the	O
Lisp	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
The	O
dialect	O
used	O
in	O
GNU	B-Application
Emacs	I-Application
is	O
known	O
as	O
Emacs	B-Operating_System
Lisp	I-Operating_System
(	O
Elisp	B-Operating_System
)	O
,	O
and	O
was	O
developed	O
expressly	O
to	O
port	O
Emacs	B-Application
to	O
GNU	B-Operating_System
and	O
Unix	B-Application
.	O
</s>
<s>
The	O
Emacs	B-Operating_System
Lisp	I-Operating_System
layer	O
sits	O
atop	O
a	O
stable	O
core	O
of	O
basic	O
services	O
and	O
platform	O
abstraction	O
written	O
in	O
the	O
C	B-Language
programming	I-Language
language	I-Language
,	O
which	O
enables	O
GNU	B-Application
Emacs	I-Application
to	O
be	O
ported	O
to	O
a	O
wide	O
variety	O
of	O
operating	B-General_Concept
systems	I-General_Concept
and	O
architectures	O
without	O
modifying	O
the	O
implementation	O
semantics	O
of	O
the	O
Lisp	B-Language
system	O
where	O
most	O
of	O
the	O
editor	O
lives	O
.	O
</s>
<s>
In	O
this	O
Lisp	B-Language
environment	O
,	O
variables	O
and	O
functions	O
can	O
be	O
modified	O
with	O
no	O
need	O
to	O
rebuild	O
or	O
restart	O
Emacs	B-Application
,	O
with	O
even	O
newly	O
redefined	O
versions	O
of	O
core	O
editor	O
features	O
being	O
asynchronously	O
compiled	O
and	O
loaded	O
into	O
the	O
live	O
environment	O
to	O
replace	O
existing	O
definitions	O
.	O
</s>
<s>
Modern	O
GNU	B-Application
Emacs	I-Application
features	O
both	O
bytecode	O
and	O
native	B-Language
code	I-Language
compilation	O
for	O
Emacs	B-Operating_System
Lisp	I-Operating_System
.	O
</s>
<s>
All	O
configuration	O
is	O
stored	O
in	O
variables	O
,	O
classes	O
,	O
and	O
data	B-General_Concept
structures	I-General_Concept
,	O
and	O
changed	O
by	O
simply	O
updating	O
these	O
live	O
.	O
</s>
<s>
The	O
use	O
of	O
a	O
Lisp	B-Language
dialect	O
in	O
this	O
case	O
is	O
a	O
key	O
advantage	O
,	O
as	O
Lisp	B-Protocol
syntax	I-Protocol
consists	O
of	O
so-called	O
symbolic	B-Protocol
expressions	I-Protocol
(	O
or	O
sexprs	B-Protocol
)	O
,	O
which	O
can	O
act	O
as	O
both	O
evaluatable	O
code	O
expressions	O
and	O
as	O
a	O
data	B-Application
serialisation	I-Application
format	I-Application
akin	O
to	O
,	O
but	O
simpler	O
and	O
more	O
general	O
than	O
,	O
widely	O
known	O
ones	O
such	O
as	O
XML	B-Protocol
,	O
JSON	B-General_Concept
,	O
and	O
YAML	B-Protocol
.	O
</s>
<s>
The	O
goal	O
of	O
Emacs	B-Application
 '	O
open	O
design	O
is	O
to	O
transparently	O
expose	O
Emacs	B-Application
 '	O
internals	O
to	O
the	O
Emacs	B-Application
user	O
during	O
normal	O
use	O
in	O
the	O
same	O
way	O
that	O
they	O
would	O
be	O
exposed	O
to	O
the	O
Emacs	B-Application
developer	O
working	O
on	O
the	O
git	B-Application
tree	I-Application
,	O
and	O
to	O
collapse	O
as	O
much	O
as	O
possible	O
of	O
the	O
distinction	O
between	O
using	O
Emacs	B-Application
and	O
programming	O
Emacs	B-Application
,	O
while	O
still	O
maintaining	O
a	O
stable	O
,	O
practical	O
environment	O
for	O
novice	O
users	O
.	O
</s>
<s>
The	O
main	O
text	B-Application
editing	I-Application
data	B-General_Concept
structure	I-General_Concept
is	O
the	O
buffer	B-General_Concept
,	O
a	O
memory	O
region	O
containing	O
data	O
(	O
usually	O
text	O
)	O
with	O
associated	O
attributes	O
.	O
</s>
<s>
The	O
point	O
:	O
the	O
editing	B-Application
cursor	I-Application
;	O
</s>
<s>
The	O
name	O
and	O
inode	B-Application
of	O
the	O
file	O
the	O
buffer	B-General_Concept
is	O
visiting	O
(	O
if	O
any	O
)	O
;	O
</s>
<s>
The	O
default	O
directory	O
,	O
where	O
any	O
OS-level	O
commands	O
will	O
be	O
executed	B-Application
from	I-Application
by	O
default	O
;	O
</s>
<s>
The	O
buffer	B-General_Concept
encoding	O
,	O
the	O
method	O
by	O
which	O
Emacs	B-Application
represents	O
buffer	B-General_Concept
data	O
to	O
the	O
user	O
;	O
</s>
<s>
and	O
a	O
variety	O
of	O
buffer	B-General_Concept
local	O
variables	O
and	O
Emacs	B-Operating_System
Lisp	I-Operating_System
state	O
.	O
</s>
<s>
Modes	O
,	O
in	O
particular	O
,	O
are	O
an	O
important	O
concept	O
in	O
Emacs	B-Application
,	O
providing	O
a	O
mechanism	O
to	O
disaggregate	O
Emacs	B-Application
 '	O
functionality	O
into	O
sets	O
of	O
behaviours	O
and	O
keybinds	O
relevant	O
to	O
specific	O
buffers	B-General_Concept
 '	O
data	O
.	O
</s>
<s>
Major	O
modes	O
provide	O
a	O
general	O
package	O
of	O
functions	O
and	O
commands	O
relevant	O
to	O
a	O
buffer	B-General_Concept
's	O
data	O
and	O
the	O
way	O
users	O
might	O
be	O
interacting	O
with	O
it	O
(	O
e.g.	O
</s>
<s>
editing	O
source	O
code	O
in	O
a	O
specific	O
language	O
,	O
editing	B-Application
hex	I-Application
,	O
viewing	O
the	O
filesystem	O
,	O
interacting	O
with	O
git	B-Application
,	O
etc	O
.	O
</s>
<s>
Minor	O
modes	O
can	O
be	O
toggled	O
on	O
or	O
off	O
both	O
locally	O
to	O
each	O
buffer	B-General_Concept
as	O
well	O
as	O
globally	O
across	O
all	O
buffers	B-General_Concept
,	O
while	O
major	O
modes	O
can	O
only	O
be	O
toggled	O
per-buffer	O
.	O
</s>
<s>
Any	O
other	O
data	O
relevant	O
to	O
a	O
buffer	B-General_Concept
but	O
not	O
bundled	O
into	O
a	O
mode	O
can	O
be	O
handled	O
by	O
simply	O
focussing	O
that	O
buffer	B-General_Concept
and	O
live	O
modifying	O
the	O
relevant	O
data	O
directly	O
.	O
</s>
<s>
Any	O
interaction	O
with	O
the	O
editor	O
(	O
like	O
key	O
presses	O
or	O
clicking	O
a	O
mouse	O
button	O
)	O
is	O
realized	O
by	O
evaluating	O
Emacs	B-Operating_System
Lisp	I-Operating_System
code	O
,	O
typically	O
a	O
command	O
,	O
which	O
is	O
a	O
function	O
explicitly	O
designed	O
for	O
interactive	O
use	O
.	O
</s>
<s>
Keys	O
can	O
be	O
arbitrarily	O
redefined	O
and	O
commands	O
can	O
also	O
be	O
accessed	O
by	O
name	O
;	O
some	O
commands	O
evaluate	O
arbitrary	O
Emacs	B-Operating_System
Lisp	I-Operating_System
code	O
provided	O
by	O
the	O
user	O
in	O
various	O
ways	O
(	O
e.g.	O
</s>
<s>
a	O
family	O
of	O
eval	O
-	O
region	O
,	O
buffer	B-General_Concept
,	O
and	O
expression	O
type	O
commands	O
)	O
.	O
</s>
<s>
Even	O
the	O
simplest	O
user	O
inputs	O
(	O
such	O
a	O
printable	O
characters	O
)	O
are	O
effectuated	O
as	O
Emacs	B-Operating_System
Lisp	I-Operating_System
functions	O
,	O
such	O
as	O
the	O
self-insert-command	O
,	O
bound	O
to	O
most	O
keyboard	O
keys	O
in	O
a	O
typical	O
text	B-Application
editing	I-Application
buffer	B-General_Concept
by	O
default	O
,	O
which	O
parameterises	O
itself	O
with	O
the	O
locale-defined	O
character	O
associated	O
with	O
the	O
key	O
used	O
to	O
call	O
it	O
.	O
</s>
<s>
For	O
example	O
,	O
pressing	O
the	O
key	O
in	O
a	O
buffer	B-General_Concept
that	O
accepts	O
text	O
input	O
evaluates	O
the	O
code	O
,	O
which	O
inserts	O
one	O
copy	O
of	O
the	O
character	O
constant	O
?	O
f	O
at	O
point	O
.	O
</s>
<s>
The	O
1	O
,	O
in	O
this	O
case	O
,	O
is	O
determined	O
by	O
what	O
Emacs	B-Application
terms	O
the	O
universal	O
argument	O
:	O
all	O
Emacs	B-Application
command	O
code	O
accepts	O
a	O
numeric	O
value	O
which	O
,	O
in	O
its	O
simplest	O
usage	O
,	O
indicates	O
repetition	O
of	O
an	O
action	O
,	O
but	O
in	O
more	O
complex	O
cases	O
(	O
where	O
repetition	O
does	O
n't	O
make	O
sense	O
)	O
can	O
yield	O
other	O
behaviours	O
.	O
</s>
<s>
Because	O
of	O
its	O
relatively	O
large	O
vocabulary	O
of	O
commands	O
,	O
Emacs	B-Application
features	O
a	O
long-established	O
command	O
language	O
,	O
to	O
concisely	O
express	O
the	O
keystrokes	O
necessary	O
to	O
perform	O
an	O
action	O
.	O
</s>
<s>
These	O
are	O
represented	O
in	O
command	O
language	O
as	O
the	O
respective	O
prefices	O
:	O
C-	O
,	O
A-	O
,	O
S-	O
,	O
M-	O
,	O
s-	O
,	O
and	O
H-	O
.	O
</s>
<s>
Thus	O
,	O
a	O
keyboard	O
shortcut	O
such	O
as	O
(	O
check	O
dependent	O
formulas	O
and	O
calculate	O
all	O
cells	O
in	O
all	O
open	O
workbooks	O
in	O
Excel	B-Application
)	O
would	O
be	O
rendered	O
in	O
Emacs	B-Application
command	O
language	O
as	O
C-A-S-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx1	O
,	O
with	O
Emacs	B-Application
scanning	O
the	O
namespace	O
of	O
contextually	O
available	O
commands	O
to	O
return	O
the	O
shortest	O
sequence	O
of	O
keystrokes	O
which	O
uniquely	O
lexicate	O
it	O
.	O
</s>
<s>
Because	O
Emacs	B-Application
predates	O
modern	O
standard	O
terminology	O
for	O
graphical	B-Application
user	I-Application
interfaces	I-Application
,	O
it	O
uses	O
somewhat	O
divergent	O
names	O
for	O
familiar	O
interface	O
elements	O
.	O
</s>
<s>
Buffers	B-General_Concept
,	O
the	O
data	O
that	O
Emacs	B-Application
users	O
interact	O
with	O
,	O
are	O
displayed	O
to	O
the	O
user	O
inside	O
windows	O
,	O
which	O
are	O
tiled	O
portions	O
of	O
the	O
terminal	O
screen	O
or	O
the	O
GUI	B-Application
window	O
,	O
which	O
Emacs	B-Application
refers	O
to	O
as	O
frames	O
;	O
in	O
modern	O
terminology	O
,	O
an	O
Emacs	B-Application
frame	O
would	O
be	O
a	O
window	O
and	O
an	O
Emacs	B-Application
window	O
would	O
be	O
a	O
split	O
.	O
</s>
<s>
Depending	O
on	O
configuration	O
,	O
windows	O
can	O
include	O
their	O
own	O
scroll	O
bars	O
,	O
line	O
numbers	O
,	O
sometimes	O
a	O
'	O
header	O
line	O
 '	O
typically	O
to	O
ease	O
navigation	O
,	O
and	O
a	O
mode	O
line	O
at	O
the	O
bottom	O
(	O
usually	O
displaying	O
buffer	B-General_Concept
name	O
,	O
the	O
active	O
modes	O
and	O
point	O
position	O
of	O
the	O
buffer	B-General_Concept
among	O
others	O
)	O
.	O
</s>
<s>
In	O
general	O
,	O
Emacs	B-Application
display	O
elements	O
(	O
windows	O
,	O
frames	O
,	O
etc	O
.	O
)	O
</s>
<s>
Buffers	B-General_Concept
are	O
not	O
associated	O
with	O
windows	O
,	O
and	O
multiple	O
windows	O
can	O
be	O
opened	O
onto	O
the	O
same	O
buffer	B-General_Concept
,	O
for	O
example	O
to	O
see	O
different	O
parts	O
of	O
a	O
long	O
text	O
side-by-side	O
without	O
scrolling	O
,	O
and	O
multiple	O
buffers	B-General_Concept
can	O
share	O
the	O
same	O
text	O
,	O
for	O
example	O
to	O
take	O
advantage	O
of	O
different	O
major	O
modes	O
in	O
a	O
mixed-language	O
file	O
.	O
</s>
<s>
Similarly	O
,	O
Emacs	B-Application
instances	O
are	O
not	O
associated	O
with	O
particular	O
frames	O
,	O
and	O
multiple	O
frames	O
can	O
be	O
opened	O
displaying	O
a	O
single	O
running	O
Emacs	B-Application
process	O
,	O
e.g.	O
</s>
<s>
a	O
frame	O
per	O
screen	O
in	O
a	O
multi-monitor	O
setup	O
,	O
or	O
a	O
terminal	O
frame	O
connected	O
via	O
ssh	B-Protocol
from	O
a	O
remote	O
system	O
and	O
a	O
graphical	O
frame	O
displaying	O
the	O
same	O
Emacs	B-Application
process	O
via	O
the	O
local	O
system	O
's	O
monitor	O
,	O
etc	O
.	O
</s>
<s>
Because	O
of	O
this	O
separation	O
of	O
concerns	O
,	O
Emacs	B-Application
can	O
display	O
roughly	O
similarly	O
on	O
any	O
device	O
more	O
complex	O
than	O
a	O
dumb	O
terminal	O
,	O
including	O
providing	O
typical	O
graphical	O
WIMP	B-Application
elements	O
on	O
sufficiently	O
featureful	O
text	O
terminals	O
-	O
though	O
graphical	O
frames	O
are	O
the	O
preferred	O
mode	O
of	O
display	O
,	O
providing	O
a	O
strict	O
superset	O
of	O
the	O
features	O
of	O
text	O
terminal	O
frames	O
.	O
</s>
<s>
Because	O
of	O
the	O
uniformity	O
of	O
Emacs	B-Application
 '	O
features	O
 '	O
definition	O
in	O
terms	O
of	O
Emacs	B-Operating_System
Lisp	I-Operating_System
,	O
what	O
counts	O
as	O
a	O
"	O
user	O
action	O
"	O
for	O
the	O
purposes	O
of	O
macro-automation	O
is	O
flexible	O
:	O
macros	O
may	O
include	O
,	O
e.g.	O
,	O
keypresses	O
,	O
commands	O
,	O
mouse	O
clicks	O
,	O
other	O
macros	O
,	O
and	O
anything	O
that	O
can	O
be	O
effectuated	O
via	O
these	O
.	O
</s>
<s>
At	O
startup	O
,	O
Emacs	B-Application
executes	O
an	O
Emacs	B-Operating_System
Lisp	I-Operating_System
script	O
named	O
(	O
recent	O
versions	O
also	O
look	O
for	O
,	O
,	O
and	O
;	O
,	O
as	O
well	O
as	O
similar	O
variations	O
on	O
.	O
</s>
<s>
Emacs	B-Application
reads	O
first	O
if	O
it	O
exists	O
,	O
and	O
it	O
can	O
be	O
used	O
to	O
configure	O
or	O
short-circuit	O
core	O
Emacs	B-Application
features	O
before	O
they	O
load	O
,	O
such	O
as	O
the	O
graphical	O
display	O
system	O
or	O
package	B-Application
manager	I-Application
.	O
</s>
<s>
Loading	O
,	O
enabling	O
and	O
initializing	O
extensions	O
(	O
Emacs	B-Application
comes	O
with	O
many	O
extensions	O
,	O
but	O
only	O
a	O
few	O
are	O
loaded	O
by	O
default	O
.	O
)	O
</s>
<s>
The	O
customize	O
extension	O
allows	O
the	O
user	O
to	O
set	O
configuration	O
properties	O
such	O
as	O
the	O
color	O
scheme	O
interactively	O
,	O
from	O
within	O
Emacs	B-Application
,	O
in	O
a	O
more	O
user-friendly	O
way	O
than	O
by	O
setting	O
variables	O
in	O
:	O
it	O
offers	O
search	O
,	O
descriptions	O
and	O
help	O
text	O
,	O
multiple	O
choice	O
inputs	O
,	O
reverting	O
to	O
defaults	O
,	O
modification	O
of	O
the	O
running	O
Emacs	B-Application
instance	O
without	O
reloading	O
,	O
and	O
other	O
conveniences	O
similar	O
to	O
the	O
preferences	O
functionality	O
of	O
other	O
programs	O
.	O
</s>
<s>
Themes	O
,	O
affecting	O
the	O
choice	O
of	O
fonts	O
and	O
colours	O
,	O
are	O
defined	O
as	O
Emacs	B-Operating_System
Lisp	I-Operating_System
files	B-Operating_System
and	O
chosen	O
through	O
the	O
customize	O
extension	O
.	O
</s>
<s>
Modes	O
,	O
which	O
support	O
editing	O
a	O
range	O
of	O
programming	O
languages	O
(	O
e.g.	O
,	O
emacs-lisp-mode	O
,	O
c-mode	O
,	O
java-mode	O
,	O
ESS	O
for	O
R	O
)	O
by	O
changing	O
fonts	O
to	O
highlight	O
the	O
code	O
and	O
keybindings	O
modified	O
(	O
forword-function	O
vs.	O
forward-page	O
)	O
.	O
</s>
<s>
The	O
first	O
Emacs	B-Application
contained	O
a	O
help	O
library	O
that	O
included	O
documentation	O
for	O
every	O
command	O
,	O
variable	O
and	O
internal	O
function	O
.	O
</s>
<s>
Because	O
of	O
this	O
,	O
Emacs	B-Application
proponents	O
described	O
the	O
software	O
as	O
self-documenting	O
in	O
that	O
it	O
presents	O
the	O
user	O
with	O
information	O
on	O
its	O
normal	O
features	O
and	O
its	O
current	O
state	O
.	O
</s>
<s>
Each	O
function	O
includes	O
a	O
documentation	O
string	O
that	O
is	O
displayed	O
to	O
the	O
user	O
on	O
request	O
,	O
a	O
practice	O
that	O
subsequently	O
spread	O
to	O
programming	O
languages	O
including	O
Lisp	B-Language
,	O
Java	B-Language
,	O
Perl	B-Language
,	O
and	O
Python	B-Language
.	O
</s>
<s>
Emacs	B-Application
also	O
has	O
a	O
built-in	O
tutorial	O
.	O
</s>
<s>
Emacs	B-Application
displays	O
instructions	O
for	O
performing	O
simple	O
editing	O
commands	O
and	O
invoking	O
the	O
tutorial	O
when	O
it	O
is	O
launched	O
with	O
no	O
file	O
to	O
edit	O
.	O
</s>
<s>
The	B-Language
Church	I-Language
of	I-Language
Emacs	I-Language
,	O
formed	O
by	O
Richard	O
Stallman	O
,	O
is	O
a	O
parody	O
religion	O
created	O
for	O
Emacs	B-Application
users	O
.	O
</s>
<s>
While	O
it	O
refers	O
to	O
vi	B-Application
as	O
the	O
editor	O
of	O
the	O
beast	O
(	O
vi-vi-vi	O
being	O
6-6-6	O
in	O
Roman	O
numerals	O
)	O
,	O
it	O
does	O
not	O
oppose	O
the	O
use	O
of	O
vi	B-Application
;	O
rather	O
,	O
it	O
calls	O
it	O
proprietary	B-Application
software	I-Application
anathema	O
.	O
</s>
<s>
The	B-Language
Church	I-Language
of	I-Language
Emacs	I-Language
has	O
its	O
own	O
newsgroup	B-Application
,	O
,	O
that	O
has	O
posts	O
purporting	O
to	O
support	O
this	O
parody	O
religion	O
.	O
</s>
<s>
Supporters	O
of	O
vi	B-Application
have	O
created	O
an	O
opposing	O
Cult	B-Language
of	I-Language
vi	I-Language
.	O
</s>
<s>
Stallman	O
has	O
jokingly	O
referred	O
to	O
himself	O
as	O
St	O
I	O
GNU	B-Operating_System
cius	O
,	O
a	O
saint	O
in	O
the	B-Language
Church	I-Language
of	I-Language
Emacs	I-Language
.	O
</s>
<s>
There	O
is	O
folklore	O
attributing	O
a	O
repetitive	O
strain	O
injury	O
colloquially	O
called	O
Emacs	B-Application
pinky	O
to	O
Emacs	B-Application
 '	O
strong	O
dependence	O
on	O
modifier	O
keys	O
,	O
although	O
there	O
have	O
not	O
been	O
any	O
studies	O
done	O
to	O
show	O
Emacs	B-Application
causes	O
more	O
such	O
problems	O
than	O
other	O
keyboard-heavy	O
computer	O
programs	O
.	O
</s>
<s>
Some	O
users	O
recommend	O
simply	O
using	O
the	O
two	O
Control	B-Device
keys	I-Device
on	O
typical	O
PC	O
keyboards	O
like	O
Shift	O
keys	O
while	O
touch	O
typing	O
to	O
avoid	O
overly	O
straining	O
the	O
left	O
pinky	O
,	O
a	O
proper	O
use	O
of	O
the	O
keyboard	O
will	O
reduce	O
the	O
RSI	O
.	O
</s>
<s>
Similar	O
techniques	O
include	O
defining	O
the	O
key	O
as	O
an	O
additional	O
Control	B-Device
key	I-Device
or	O
transposing	O
the	O
Control	O
and	O
Meta	O
keys	O
.	O
</s>
<s>
Software	O
,	O
such	O
as	O
xwrits	O
or	O
the	O
built-in	O
in	O
Emacs	B-Application
,	O
that	O
reminds	O
the	O
user	O
to	O
take	O
regularly	O
scheduled	O
breaks	O
.	O
</s>
<s>
Customizing	O
the	O
whole	O
keyboard	O
layout	O
to	O
move	O
statistically	O
frequent	O
Emacs	B-Application
keys	O
to	O
more	O
appropriate	O
places	O
.	O
</s>
<s>
Packages	O
such	O
as	O
ace-jump-mode	O
or	O
Emacs	B-Operating_System
Lisp	I-Operating_System
extensions	O
that	O
provide	O
similar	O
functionality	O
of	O
tiered	O
navigation	O
,	O
first	O
asking	O
for	O
a	O
character	O
then	O
replacing	O
occurrences	O
of	O
the	O
character	O
with	O
access	O
keys	O
for	O
cursor	B-Application
movement	O
.	O
</s>
<s>
evil-mode	O
,	O
an	O
advanced	O
Vim	B-Application
emulation	O
layer	O
.	O
</s>
<s>
god-mode	O
,	O
which	O
provides	O
an	O
approach	O
similar	O
to	O
vim	B-Application
's	O
with	O
a	O
mode	O
for	O
entering	O
Emacs	B-Application
commands	O
without	O
modifier	O
keys	O
.	O
</s>
<s>
Using	O
customized	O
key	O
layout	O
offered	O
by	O
Spacemacs	B-Application
and	O
Doom	O
Emacs	B-Application
,	O
projects	O
where	O
key	O
is	O
used	O
as	O
the	O
main	O
key	O
for	O
initiating	O
control	O
sequences	O
.	O
</s>
<s>
StickyKeys	B-Device
,	O
which	O
turns	O
key	O
sequences	O
into	O
key	O
combinations	O
.	O
</s>
<s>
Emacs	B-Application
 '	O
built-in	O
viper-mode	O
that	O
allows	O
use	O
of	O
the	O
vi	B-Application
key	O
layout	O
for	O
basic	O
text	B-Application
editing	I-Application
and	O
the	O
Emacs	B-Application
scheme	O
for	O
more	O
advanced	O
features	O
.	O
</s>
<s>
Giving	O
a	O
dual	O
role	O
to	O
a	O
more-comfortably	O
accessed	O
key	O
such	O
as	O
the	O
space	B-Device
bar	I-Device
so	O
that	O
it	O
functions	O
as	O
a	O
Control	B-Device
key	I-Device
when	O
pressed	O
in	O
combination	O
with	O
other	O
keys	O
.	O
</s>
<s>
Ergonomic	B-Device
keyboards	I-Device
or	O
keyboards	O
with	O
a	O
greater	O
number	O
of	O
keys	O
adjacent	O
to	O
the	O
space	B-Device
bar	I-Device
,	O
such	O
as	O
Japanese	O
keyboards	O
,	O
allow	O
thumb	O
control	O
of	O
other	O
modifier	O
keys	O
too	O
like	O
Meta	O
or	O
Shift	O
.	O
</s>
<s>
Driving	O
Emacs	B-Application
through	O
voice	O
input	O
.	O
</s>
<s>
Hardware	O
solutions	O
include	O
special	O
keyboards	O
such	O
as	O
Kinesis	B-Device
's	I-Device
Contoured	I-Device
Keyboard	I-Device
,	O
which	O
places	O
the	O
modifier	O
keys	O
where	O
they	O
can	O
easily	O
be	O
operated	O
by	O
the	O
thumb	O
,	O
or	O
the	O
Microsoft	B-Device
Natural	I-Device
keyboard	I-Device
,	O
whose	O
large	O
modifier	O
keys	O
are	O
placed	O
symmetrically	O
on	O
both	O
sides	O
of	O
the	O
keyboard	O
and	O
can	O
be	O
pressed	O
with	O
the	O
palm	O
of	O
the	O
hand	O
.	O
</s>
<s>
The	O
Emacs	B-Application
pinky	O
is	O
a	O
relatively	O
recent	O
development	O
.	O
</s>
<s>
The	O
Space-cadet	B-Device
keyboard	I-Device
on	O
which	O
Emacs	B-Application
was	O
developed	O
had	O
oversized	O
Control	B-Device
keys	I-Device
that	O
were	O
adjacent	O
to	O
the	O
space	B-Device
bar	I-Device
and	O
were	O
easy	O
to	O
reach	O
with	O
the	O
thumb	O
.	O
</s>
<s>
The	O
word	O
emacs	B-Application
is	O
sometimes	O
pluralized	O
as	O
emacsen	B-Application
,	O
by	O
phonetic	O
analogy	O
with	O
boxen	O
and	O
VAXen	B-Device
,	O
referring	O
to	O
different	O
varieties	O
of	O
Emacs	B-Application
.	O
</s>
