<s>
Comparison	B-Operating_System
of	I-Operating_System
user	I-Operating_System
features	I-Operating_System
of	I-Operating_System
operating	I-Operating_System
systems	I-Operating_System
refers	O
to	O
a	O
comparison	O
of	O
the	O
general	O
user	O
features	O
of	O
major	O
operating	B-General_Concept
systems	I-General_Concept
in	O
a	O
narrative	O
format	O
.	O
</s>
<s>
It	O
does	O
not	O
encompass	O
a	O
full	O
exhaustive	O
comparison	O
or	O
description	O
of	O
all	O
technical	O
details	O
of	O
all	O
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
It	O
also	O
includes	O
the	O
most	O
important	O
features	O
of	O
the	O
operating	B-General_Concept
system	I-General_Concept
's	O
origins	O
,	O
historical	O
development	O
,	O
and	O
role	O
.	O
</s>
<s>
An	O
operating	B-General_Concept
system	I-General_Concept
(	O
OS	O
)	O
is	O
system	B-Application
software	I-Application
that	O
manages	O
computer	O
hardware	O
,	O
software	B-Application
resources	O
,	O
and	O
provides	O
common	O
services	B-Operating_System
for	O
computer	O
programs	O
.	O
</s>
<s>
Time-sharing	B-General_Concept
operating	I-General_Concept
systems	I-General_Concept
schedule	O
tasks	O
for	O
efficient	O
use	O
of	O
the	O
system	O
and	O
may	O
also	O
include	O
accounting	O
software	B-Application
for	O
cost	O
allocation	O
of	O
processor	O
time	O
,	O
mass	B-Device
storage	I-Device
,	O
printing	O
,	O
and	O
other	O
resources	O
.	O
</s>
<s>
For	O
hardware	O
functions	O
such	O
as	O
input	B-General_Concept
and	I-General_Concept
output	I-General_Concept
and	O
memory	B-General_Concept
allocation	I-General_Concept
,	O
the	O
operating	B-General_Concept
system	I-General_Concept
acts	O
as	O
an	O
intermediary	O
between	O
programs	O
and	O
the	O
computer	O
hardware	O
,	O
although	O
the	O
application	O
code	O
is	O
usually	O
executed	O
directly	O
by	O
the	O
hardware	O
and	O
frequently	O
makes	O
system	B-Operating_System
calls	I-Operating_System
to	O
an	O
OS	O
function	O
or	O
is	O
interrupted	O
by	O
it	O
.	O
</s>
<s>
Operating	B-General_Concept
systems	I-General_Concept
are	O
found	O
on	O
many	O
devices	O
that	O
contain	O
a	O
computer	O
from	O
cellular	O
phones	O
and	O
video	B-Device
game	I-Device
consoles	I-Device
to	O
web	B-Application
servers	I-Application
and	O
supercomputers	B-Architecture
.	O
</s>
<s>
,	O
the	O
dominant	O
general-purpose	O
desktop	B-General_Concept
operating	I-General_Concept
system	I-General_Concept
is	O
Microsoft	B-Application
Windows	I-Application
with	O
a	O
market	O
share	O
of	O
around	O
74.14	O
%	O
.	O
</s>
<s>
macOS	B-Application
by	O
Apple	O
Inc	O
.	O
is	O
in	O
second	O
place	O
(	O
15.33	O
%	O
)	O
,	O
and	O
the	O
varieties	O
of	O
Linux	B-Application
are	O
collectively	O
in	O
third	O
place	O
(	O
2.91	O
%	O
)	O
.	O
</s>
<s>
In	O
the	O
mobile	B-Operating_System
sector	O
,	O
including	O
both	O
smartphones	B-Application
and	O
tablets	B-Device
,	O
Android	B-Application
is	O
dominant	O
with	O
a	O
market	O
share	O
of	O
71%	O
,	O
followed	O
by	O
Apple	O
's	O
iOS	B-Application
with	O
28%	O
;	O
for	O
smartphones	B-Application
alone	O
,	O
Android	B-Application
has	O
72%	O
and	O
iOS	B-Application
has	O
28%	O
.	O
</s>
<s>
Linux	B-Application
distributions	I-Application
are	O
dominant	O
in	O
the	O
server	O
and	O
supercomputing	B-Architecture
sectors	O
.	O
</s>
<s>
Other	O
specialized	O
classes	O
of	O
operating	B-General_Concept
systems	I-General_Concept
(	O
special-purpose	O
operating	B-General_Concept
systems	I-General_Concept
)	O
)	O
,	O
such	O
as	O
embedded	B-Architecture
and	O
real-time	O
systems	O
,	O
exist	O
for	O
many	O
applications	B-Application
.	O
</s>
<s>
Security-focused	O
operating	B-General_Concept
systems	I-General_Concept
also	O
exist	O
.	O
</s>
<s>
Some	O
operating	B-General_Concept
systems	I-General_Concept
have	O
low	O
system	O
requirements	O
(	O
i.e.	O
</s>
<s>
light-weight	B-Operating_System
Linux	I-Operating_System
distribution	I-Operating_System
)	O
.	O
</s>
<s>
Some	O
operating	B-General_Concept
systems	I-General_Concept
require	O
installation	O
or	O
may	O
come	O
pre-installed	O
with	O
purchased	O
computers	O
(	O
OEM-installation	O
)	O
,	O
whereas	O
others	O
may	O
run	O
directly	O
from	O
media	O
(	O
i.e.	O
</s>
<s>
MS-DOS	B-Application
(	O
acronym	O
for	O
Microsoft	B-Application
Disk	I-Application
Operating	I-Application
System	I-Application
)	O
is	O
an	O
operating	B-General_Concept
system	I-General_Concept
for	O
x86-based	O
personal	O
computers	O
mostly	O
developed	O
by	O
Microsoft	O
.	O
</s>
<s>
Collectively	O
,	O
MS-DOS	B-Application
,	O
its	O
rebranding	O
as	O
IBM	O
PC	O
DOS	O
,	O
and	O
some	O
operating	B-General_Concept
systems	I-General_Concept
attempting	O
to	O
be	O
compatible	O
with	O
MS-DOS	B-Application
,	O
are	O
sometimes	O
referred	O
to	O
as	O
"	O
DOS	O
"	O
(	O
which	O
is	O
also	O
the	O
generic	O
acronym	O
for	O
disk	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
)	O
.	O
</s>
<s>
MS-DOS	B-Application
was	O
the	O
main	O
operating	B-General_Concept
system	I-General_Concept
for	O
IBM	O
PC	O
compatible	O
personal	O
computers	O
during	O
the	O
1980s	O
,	O
from	O
which	O
point	O
it	O
was	O
gradually	O
superseded	O
by	O
operating	B-General_Concept
systems	I-General_Concept
offering	O
a	O
graphical	B-Application
user	I-Application
interface	I-Application
(	O
GUI	B-Application
)	O
,	O
in	O
various	O
generations	O
of	O
the	O
graphical	B-Application
Microsoft	B-Application
Windows	I-Application
operating	I-Application
system	I-Application
.	O
</s>
<s>
Although	O
MS-DOS	B-Application
and	O
PCDOS	O
were	O
initially	O
developed	O
in	O
parallel	O
by	O
Microsoft	O
and	O
IBM	O
,	O
the	O
two	O
products	O
diverged	O
after	O
twelve	O
years	O
,	O
in	O
1993	O
,	O
with	O
recognizable	O
differences	O
in	O
compatibility	O
,	O
syntax	O
,	O
and	O
capabilities	O
.	O
</s>
<s>
During	O
its	O
lifetime	O
,	O
several	O
competing	O
products	O
were	O
released	O
for	O
the	O
x86	B-Operating_System
platform	O
,	O
and	O
MS-DOS	B-Application
went	O
through	O
eight	O
versions	O
,	O
until	O
development	O
ceased	O
in	O
2000	O
.	O
</s>
<s>
Initially	O
,	O
MS-DOS	B-Application
was	O
targeted	O
at	O
Intel	B-General_Concept
8086	I-General_Concept
processors	O
running	O
on	O
computer	O
hardware	O
using	O
floppy	B-Device
disks	I-Device
to	O
store	O
and	O
access	O
not	O
only	O
the	O
operating	B-General_Concept
system	I-General_Concept
,	O
but	O
application	B-Application
software	I-Application
and	O
user	O
data	O
as	O
well	O
.	O
</s>
<s>
Progressive	O
version	O
releases	O
delivered	O
support	O
for	O
other	O
mass	B-Device
storage	I-Device
media	O
in	O
ever	O
greater	O
sizes	O
and	O
formats	O
,	O
along	O
with	O
added	O
feature	O
support	O
for	O
newer	O
processors	O
and	O
rapidly	O
evolving	O
computer	O
architectures	O
.	O
</s>
<s>
Ultimately	O
,	O
it	O
was	O
the	O
key	O
product	O
in	O
Microsoft	O
's	O
development	O
from	O
a	O
programming	O
language	O
company	O
to	O
a	O
diverse	O
software	B-Application
development	O
firm	O
,	O
providing	O
the	O
company	O
with	O
essential	O
revenue	O
and	O
marketing	O
resources	O
.	O
</s>
<s>
It	O
was	O
also	O
the	O
underlying	O
basic	O
operating	B-General_Concept
system	I-General_Concept
on	O
which	O
early	O
versions	O
of	O
Windows	O
ran	O
as	O
a	O
GUI	B-Application
.	O
</s>
<s>
Microsoft	B-Application
Windows	I-Application
,	O
commonly	O
referred	O
to	O
as	O
Windows	O
,	O
is	O
a	O
group	O
of	O
several	O
proprietary	B-Application
graphical	B-Application
operating	B-General_Concept
system	I-General_Concept
families	O
,	O
all	O
of	O
which	O
are	O
developed	O
and	O
marketed	O
by	O
Microsoft	O
.	O
</s>
<s>
Active	O
Microsoft	B-Application
Windows	I-Application
families	O
include	O
Windows	B-Device
NT	I-Device
and	O
Windows	B-Operating_System
IoT	I-Operating_System
;	O
these	O
may	O
encompass	O
subfamilies	O
,	O
(	O
e.g.	O
</s>
<s>
Windows	B-Device
Server	I-Device
or	O
Windows	B-Operating_System
Embedded	I-Operating_System
Compact	I-Operating_System
)	O
(	O
Windows	B-Operating_System
CE	I-Operating_System
)	O
.	O
</s>
<s>
Defunct	O
Microsoft	B-Application
Windows	I-Application
families	O
include	O
Windows	O
9x	O
,	O
Windows	B-Operating_System
Mobile	I-Operating_System
,	O
and	O
Windows	B-Protocol
Phone	I-Protocol
.	O
</s>
<s>
Microsoft	O
introduced	O
an	O
operating	B-Application
environment	I-Application
named	O
Windows	O
on	O
20	O
November	O
1985	O
,	O
as	O
a	O
graphical	B-Application
operating	B-Operating_System
system	I-Operating_System
shell	I-Operating_System
for	O
MS-DOS	B-Application
in	O
response	O
to	O
the	O
growing	O
interest	O
in	O
graphical	B-Application
user	I-Application
interfaces	I-Application
(	O
GUIs	B-Application
)	O
.	O
</s>
<s>
Microsoft	B-Application
Windows	I-Application
came	O
to	O
dominate	O
the	O
world	O
's	O
personal	O
computer	O
(	O
PC	O
)	O
market	O
with	O
over	B-Operating_System
90%	I-Operating_System
market	I-Operating_System
share	I-Operating_System
,	O
overtaking	O
Mac	B-Application
OS	I-Application
,	O
which	O
had	O
been	O
introduced	O
in	O
1984	O
,	O
while	O
Microsoft	O
has	O
in	O
2020	O
lost	O
its	O
dominance	O
of	O
the	O
consumer	O
operating	B-General_Concept
system	I-General_Concept
market	O
,	O
with	O
Windows	O
down	O
to	O
30%	O
,	O
lower	O
than	O
Apple	O
's	O
31%	O
mobile-only	O
share	O
(	O
65%	O
for	O
desktop	B-General_Concept
operating	I-General_Concept
systems	I-General_Concept
only	O
,	O
i.e.	O
</s>
<s>
"	O
PCs	O
"	O
vs.	O
Apple	O
's	O
28%	O
desktop	O
share	O
)	O
in	O
its	O
home	O
market	O
,	O
the	O
US	O
,	O
and	O
32%	O
globally	O
(	O
77%	O
for	O
desktops	O
)	O
,	O
where	O
Google	B-Application
's	I-Application
Android	I-Application
leads	O
.	O
</s>
<s>
Apple	O
came	O
to	O
see	O
Windows	O
as	O
an	O
unfair	O
encroachment	O
on	O
their	O
innovation	O
in	O
GUI	B-Application
development	O
as	O
implemented	O
on	O
products	O
such	O
as	O
the	O
Lisa	B-Device
and	O
Macintosh	B-Device
(	O
eventually	O
settled	O
in	O
court	O
in	O
Microsoft	O
's	O
favor	O
in	O
1993	O
)	O
.	O
</s>
<s>
,	O
on	O
PCs	O
,	O
Windows	O
is	O
still	O
the	O
most	O
popular	O
operating	B-General_Concept
system	I-General_Concept
in	O
all	O
countries	O
.	O
</s>
<s>
However	O
,	O
in	O
2014	O
,	O
Microsoft	O
admitted	O
losing	O
the	O
majority	O
of	O
the	O
overall	O
operating	B-General_Concept
system	I-General_Concept
market	O
to	O
Android	B-Application
,	O
because	O
of	O
the	O
massive	O
growth	O
in	O
sales	O
of	O
Android	B-Application
smartphones	B-Application
.	O
</s>
<s>
In	O
2014	O
,	O
the	O
number	O
of	O
Windows	O
devices	O
sold	O
was	O
less	O
than	O
25%	O
that	O
of	O
Android	B-Application
devices	O
sold	O
.	O
</s>
<s>
This	O
comparison	O
,	O
however	O
,	O
may	O
not	O
be	O
fully	O
relevant	O
,	O
as	O
the	O
two	O
operating	B-General_Concept
systems	I-General_Concept
traditionally	O
target	O
different	O
platforms	O
.	O
</s>
<s>
,	O
the	O
most	O
recent	O
version	O
of	O
Windows	O
for	O
PCs	O
,	O
tablets	B-Device
and	O
embedded	B-Architecture
devices	I-Architecture
is	O
Windows	B-Operating_System
10	I-Operating_System
,	O
version	O
20H2	O
.	O
</s>
<s>
The	O
most	O
recent	O
version	O
for	O
server	B-Application
computers	I-Application
is	O
Windows	B-Device
Server	I-Device
,	O
version	O
20H2	O
.	O
</s>
<s>
A	O
specialized	O
version	O
of	O
Windows	O
also	O
runs	O
on	O
the	B-Device
Xbox	I-Device
One	I-Device
video	B-Device
game	I-Device
console	I-Device
.	O
</s>
<s>
Windows	B-Application
95	I-Application
introduced	O
a	O
redesigned	O
shell	B-Operating_System
based	O
around	O
a	O
desktop	B-Application
metaphor	I-Application
;	O
File	O
shortcuts	O
(	O
also	O
known	O
as	O
shell	B-Operating_System
links	O
)	O
were	O
introduced	O
and	O
the	O
desktop	O
was	O
re-purposed	O
to	O
hold	O
shortcuts	O
to	O
applications	B-Application
,	O
files	O
and	O
folders	O
,	O
reminiscent	O
of	O
Mac	B-Application
OS	I-Application
.	O
</s>
<s>
In	O
Windows	B-Application
3.1	I-Application
the	O
desktop	O
was	O
used	O
to	O
display	O
icons	O
of	O
running	O
applications	B-Application
.	O
</s>
<s>
In	O
Windows	B-Application
95	I-Application
,	O
the	O
currently	O
running	O
applications	B-Application
were	O
displayed	O
as	O
buttons	O
on	O
a	O
taskbar	O
across	O
the	O
bottom	O
of	O
the	O
screen	O
.	O
</s>
<s>
The	O
taskbar	O
also	O
contained	O
a	O
notification	O
area	O
used	O
to	O
display	O
icons	O
for	O
background	O
applications	B-Application
,	O
a	O
volume	O
control	O
and	O
the	O
current	O
time	O
.	O
</s>
<s>
The	O
Start	O
menu	O
,	O
invoked	O
by	O
clicking	O
the	O
"	O
Start	O
"	O
button	O
on	O
the	O
taskbar	O
or	O
by	O
pressing	O
the	O
Windows	B-Device
key	I-Device
,	O
was	O
introduced	O
as	O
an	O
additional	O
means	O
of	O
launching	O
applications	B-Application
or	O
opening	O
documents	O
.	O
</s>
<s>
While	O
maintaining	O
the	O
program	O
groups	O
used	O
by	O
its	O
predecessor	O
Program	O
Manager	O
,	O
it	O
also	O
displayed	O
applications	B-Application
within	O
cascading	O
sub-menus	O
.	O
</s>
<s>
The	O
previous	O
File	B-Application
Manager	I-Application
program	O
was	O
replaced	O
by	O
Windows	B-Protocol
Explorer	I-Protocol
and	O
the	O
Explorer-based	O
Control	O
Panel	O
and	O
several	O
other	O
special	B-General_Concept
folders	I-General_Concept
were	O
added	O
such	O
as	O
My	B-General_Concept
Computer	I-General_Concept
,	O
Dial	O
Up	O
Networking	O
,	O
Recycle	O
Bin	O
,	O
Network	O
Neighborhood	O
,	O
My	O
Documents	O
,	O
Recent	O
documents	O
,	O
Fonts	O
,	O
Printers	O
,	O
and	O
My	B-Application
Briefcase	I-Application
among	O
others	O
.	O
</s>
<s>
The	O
user	B-Application
interface	I-Application
looked	O
dramatically	O
different	O
from	O
prior	O
versions	O
of	O
Windows	O
,	O
but	O
its	O
design	O
language	O
did	O
not	O
have	O
a	O
special	O
name	O
like	O
Metro	O
,	O
Aqua	B-Application
or	O
Material	B-Application
Design	I-Application
.	O
</s>
<s>
Internally	O
it	O
was	O
called	O
"	O
the	O
new	O
shell	B-Operating_System
"	O
and	O
later	O
simply	O
"	O
the	O
shell	B-Operating_System
"	O
.	O
</s>
<s>
The	O
subproject	O
within	O
Microsoft	O
to	O
develop	O
the	O
new	O
shell	B-Operating_System
was	O
internally	O
known	O
as	O
"	O
Stimpy	O
"	O
.	O
</s>
<s>
In	O
1994	O
,	O
Microsoft	O
designers	O
Mark	O
Malamud	O
and	O
Erik	O
Gavriluk	O
approached	O
Brian	O
Eno	O
to	O
compose	O
music	O
for	O
the	O
Windows	B-Application
95	I-Application
project	O
.	O
</s>
<s>
The	O
result	O
was	O
the	O
six-second	O
start-up	O
music-sound	O
of	O
the	O
Windows	B-Application
95	I-Application
operating	B-General_Concept
system	I-General_Concept
,	O
The	O
Microsoft	O
Sound	O
and	O
it	O
was	O
first	O
released	O
as	O
a	O
startup	O
sound	O
in	O
May	O
1995	O
on	O
Windows	B-Application
95	I-Application
May	O
Test	O
Release	O
build	O
468	O
.	O
</s>
<s>
When	O
released	O
for	O
Windows	B-Application
95	I-Application
and	O
Windows	B-Device
NT	I-Device
4.0	O
,	O
Internet	B-Protocol
Explorer	I-Protocol
4	I-Protocol
came	O
with	O
an	O
optional	O
Windows	O
Desktop	O
Update	O
,	O
which	O
modified	O
the	O
shell	B-Operating_System
to	O
provide	O
several	O
additional	O
updates	O
to	O
Windows	B-Protocol
Explorer	I-Protocol
,	O
including	O
a	O
Quick	O
Launch	O
toolbar	O
,	O
and	O
new	O
features	O
integrated	O
with	O
Internet	O
Explorer	O
,	O
such	O
as	O
Active	O
Desktop	O
(	O
which	O
allowed	O
Internet	O
content	O
to	O
be	O
displayed	O
directly	O
on	O
the	O
desktop	O
)	O
.	O
</s>
<s>
Some	O
of	O
the	O
user	B-Application
interface	I-Application
elements	O
introduced	O
in	O
Windows	B-Application
95	I-Application
,	O
such	O
as	O
the	O
desktop	O
,	O
taskbar	O
,	O
Start	O
menu	O
and	O
Windows	B-Protocol
Explorer	I-Protocol
file	B-Application
manager	I-Application
,	O
remained	O
fundamentally	O
unchanged	O
on	O
future	O
versions	O
of	O
Windows	O
.	O
</s>
<s>
A	O
new	O
iteration	O
of	O
the	O
Start	O
menu	O
is	O
used	O
on	O
the	O
Windows	B-Operating_System
10	I-Operating_System
desktop	O
,	O
with	O
a	O
list	O
of	O
places	O
and	O
other	O
options	O
on	O
the	O
left	O
side	O
,	O
and	O
tiles	O
representing	O
applications	B-Application
on	O
the	O
right	O
.	O
</s>
<s>
The	O
menu	O
can	O
be	O
resized	O
,	O
and	O
expanded	O
into	O
a	O
full-screen	O
display	O
,	O
which	O
is	O
the	O
default	O
option	O
in	O
Tablet	B-Device
mode	O
.	O
</s>
<s>
A	O
new	O
virtual	B-Application
desktop	I-Application
system	O
was	O
added	O
.	O
</s>
<s>
A	O
feature	O
known	O
as	O
Task	O
View	O
displays	O
all	O
open	O
windows	O
and	O
allows	O
users	O
to	O
switch	O
between	O
them	O
,	O
or	O
switch	O
between	O
multiple	O
workspaces	B-Application
.	O
</s>
<s>
Windows	B-Operating_System
10	I-Operating_System
is	O
designed	O
to	O
adapt	O
its	O
user	B-Application
interface	I-Application
based	O
on	O
the	O
type	O
of	O
device	O
being	O
used	O
and	O
available	O
input	O
methods	O
.	O
</s>
<s>
It	O
offers	O
two	O
separate	O
user	B-Application
interface	I-Application
modes	O
:	O
a	O
user	B-Application
interface	I-Application
optimized	O
for	O
mouse	O
and	O
keyboard	O
,	O
and	O
a	O
"	O
Tablet	B-Device
mode	O
"	O
designed	O
for	O
touchscreens	O
.	O
</s>
<s>
Users	O
can	O
toggle	O
between	O
these	O
two	O
modes	O
at	O
any	O
time	O
,	O
and	O
Windows	O
can	O
prompt	O
or	O
automatically	O
switch	O
when	O
certain	O
events	O
occur	O
,	O
such	O
as	O
disabling	O
Tablet	B-Device
mode	O
on	O
a	O
tablet	B-Device
if	O
a	O
keyboard	O
or	O
mouse	O
is	O
plugged	O
in	O
,	O
or	O
when	O
a	O
2-in-1	B-Device
PC	I-Device
is	O
switched	O
to	O
its	O
laptop	B-Device
state	O
.	O
</s>
<s>
In	O
Tablet	B-Device
mode	O
,	O
programs	O
default	O
to	O
a	O
maximized	O
view	O
,	O
and	O
the	O
taskbar	O
contains	O
a	O
back	O
button	O
and	O
hides	O
buttons	O
for	O
opened	O
or	O
pinned	O
programs	O
by	O
default	O
;	O
Task	O
View	O
is	O
used	O
instead	O
to	O
switch	O
between	O
programs	O
.	O
</s>
<s>
The	O
classic	B-Application
Mac	I-Application
OS	I-Application
(	O
System	B-Application
Software	I-Application
)	O
is	O
the	O
series	O
of	O
operating	B-General_Concept
systems	I-General_Concept
developed	O
for	O
the	O
Macintosh	B-Device
family	O
of	O
personal	O
computers	O
by	O
Apple	O
Inc	O
.	O
from	O
1984	O
to	O
2001	O
,	O
starting	O
with	O
System	B-Operating_System
1	I-Operating_System
and	O
ending	O
with	O
Mac	B-Operating_System
OS	I-Operating_System
9	I-Operating_System
.	O
</s>
<s>
The	O
Macintosh	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
is	O
credited	O
with	O
having	O
popularized	O
the	O
graphical	B-Application
user	I-Application
interface	I-Application
concept	O
.	O
</s>
<s>
It	O
was	O
included	O
with	O
every	O
Macintosh	B-Device
that	O
was	O
sold	O
during	O
the	O
era	O
in	O
which	O
it	O
was	O
developed	O
,	O
and	O
many	O
updates	O
to	O
the	O
system	B-Application
software	I-Application
were	O
done	O
in	O
conjunction	O
with	O
the	O
introduction	O
of	O
new	O
Macintosh	B-Application
systems	I-Application
.	O
</s>
<s>
Apple	O
released	O
the	O
original	B-Device
Macintosh	I-Device
on	O
24	O
January	O
1984	O
.	O
</s>
<s>
The	O
first	B-Operating_System
version	I-Operating_System
of	I-Operating_System
the	I-Operating_System
system	I-Operating_System
software	I-Operating_System
,	O
which	O
had	O
no	O
official	O
name	O
,	O
was	O
partially	O
based	O
on	O
the	O
Lisa	B-Device
OS	O
,	O
which	O
Apple	O
previously	O
released	O
for	O
the	O
Lisa	B-Device
computer	O
in	O
1983	O
.	O
</s>
<s>
As	O
part	O
of	O
an	O
agreement	O
allowing	O
Xerox	O
to	O
buy	O
shares	O
in	O
Apple	O
at	O
a	O
favorable	O
price	O
,	O
it	O
also	O
used	O
concepts	O
from	O
the	O
Xerox	O
PARC	O
Alto	B-Device
computer	O
,	O
which	O
former	O
Apple	O
CEO	O
Steve	O
Jobs	O
and	O
other	O
Lisa	B-Device
team	O
members	O
had	O
previewed	O
.	O
</s>
<s>
This	O
operating	B-General_Concept
system	I-General_Concept
consisted	O
of	O
the	O
Macintosh	B-Device
Toolbox	I-Device
ROM	O
and	O
the	O
"	O
System	O
Folder	O
"	O
,	O
a	O
set	O
of	O
files	O
that	O
were	O
loaded	O
from	O
disk	O
.	O
</s>
<s>
The	O
name	O
Macintosh	B-Application
System	I-Application
Software	I-Application
came	O
into	O
use	O
in	O
1987	O
with	O
System	O
5	O
.	O
</s>
<s>
Apple	O
rebranded	O
the	O
system	O
as	O
Mac	B-Application
OS	I-Application
in	O
1996	O
,	O
starting	O
officially	O
with	O
version	O
7.6	O
,	O
due	O
in	O
part	O
to	O
its	O
Macintosh	B-Device
clone	O
program	O
.	O
</s>
<s>
That	O
program	O
ended	O
after	O
the	O
release	O
of	O
Mac	B-Operating_System
OS	I-Operating_System
8	I-Operating_System
in	O
1997	O
.	O
</s>
<s>
The	O
last	O
major	O
release	O
of	O
the	O
system	O
was	O
Mac	B-Operating_System
OS	I-Operating_System
9	I-Operating_System
in	O
1999	O
.	O
</s>
<s>
Initial	O
versions	O
of	O
the	O
System	B-Application
Software	I-Application
ran	O
one	O
application	O
at	O
a	O
time	O
.	O
</s>
<s>
With	O
the	O
Macintosh	B-Device
512K	I-Device
,	O
a	O
system	O
extension	O
called	O
the	O
Switcher	O
was	O
developed	O
to	O
use	O
this	O
additional	O
memory	O
to	O
allow	O
multiple	O
programs	O
to	O
remain	O
loaded	O
.	O
</s>
<s>
The	B-Application
software	I-Application
of	O
each	O
loaded	O
program	O
used	O
the	O
memory	O
exclusively	O
;	O
only	O
when	O
activated	O
by	O
the	O
Switcher	O
did	O
the	O
program	O
appear	O
,	O
even	O
the	O
Finder	B-Application
's	O
desktop	O
.	O
</s>
<s>
With	O
the	O
introduction	O
of	O
System	O
5	O
,	O
a	O
cooperative	B-Operating_System
multitasking	I-Operating_System
extension	O
called	O
MultiFinder	O
was	O
added	O
,	O
which	O
allowed	O
content	O
in	O
windows	O
of	O
each	O
program	O
to	O
remain	O
in	O
a	O
layered	O
view	O
over	O
the	O
desktop	O
,	O
and	O
was	O
later	O
integrated	O
into	O
System	O
7	O
as	O
part	O
of	O
the	O
operating	B-General_Concept
system	I-General_Concept
along	O
with	O
support	O
for	O
virtual	B-Architecture
memory	I-Architecture
.	O
</s>
<s>
By	O
the	O
mid-1990s	O
,	O
however	O
,	O
contemporary	O
operating	B-General_Concept
systems	I-General_Concept
such	O
as	O
Windows	B-Device
NT	I-Device
,	O
OS/2	B-Application
,	O
and	O
NeXTSTEP	B-Application
had	O
all	O
brought	O
pre-emptive	O
multitasking	B-Operating_System
,	O
protected	B-General_Concept
memory	I-General_Concept
,	O
access	O
controls	O
,	O
and	O
multi-user	B-Operating_System
capabilities	O
to	O
desktop	B-Device
computers	I-Device
,	O
The	O
Macintosh	B-Device
's	O
limited	O
memory	B-General_Concept
management	I-General_Concept
and	O
susceptibility	O
to	O
conflicts	O
among	O
extensions	B-Operating_System
that	O
provide	O
additional	O
functionality	O
,	O
such	O
as	O
networking	O
or	O
support	O
for	O
a	O
particular	O
device	O
,	O
led	O
to	O
significant	O
criticism	O
of	O
the	O
operating	B-General_Concept
system	I-General_Concept
,	O
and	O
was	O
a	O
factor	O
in	O
Apple	O
's	O
declining	O
market	O
share	O
at	O
the	O
time	O
.	O
</s>
<s>
After	O
two	O
aborted	O
attempts	O
at	O
creating	O
a	O
successor	O
to	O
the	O
Macintosh	B-Application
System	I-Application
Software	I-Application
called	O
Taligent	B-Operating_System
and	O
Copland	B-Application
,	O
and	O
a	O
four-year	B-Operating_System
development	I-Operating_System
effort	I-Operating_System
spearheaded	O
by	O
Steve	O
Jobs	O
 '	O
return	O
to	O
Apple	O
in	O
1997	O
,	O
Apple	O
replaced	O
Mac	B-Application
OS	I-Application
with	O
a	O
new	O
operating	B-General_Concept
system	I-General_Concept
in	O
2001	O
named	O
Mac	B-Application
OS	I-Application
X	I-Application
;	O
the	O
X	B-Operating_System
signifying	O
the	O
underlying	O
Unix	B-Application
system	I-Application
family	O
base	O
shared	O
with	O
Jobs	O
 '	O
development	O
of	O
the	O
NeXTSTEP	B-Application
operating	B-General_Concept
systems	I-General_Concept
on	O
the	O
NeXT	O
computer	O
.	O
</s>
<s>
It	O
retained	O
most	O
of	O
the	O
user	B-Application
interface	I-Application
design	O
elements	O
of	O
the	O
classic	B-Application
Mac	I-Application
OS	I-Application
,	O
and	O
there	O
was	O
some	O
overlap	O
of	O
application	B-Application
frameworks	I-Application
for	O
compatibility	O
,	O
but	O
the	O
two	O
operating	B-General_Concept
systems	I-General_Concept
otherwise	O
have	O
completely	O
different	O
origins	O
and	O
architectures	O
.	O
</s>
<s>
The	O
final	O
updates	O
to	O
Mac	B-Operating_System
OS	I-Operating_System
9	I-Operating_System
released	O
in	O
2001	O
provided	O
interoperability	O
with	O
Mac	B-Application
OS	I-Application
X	I-Application
.	O
</s>
<s>
The	O
name	O
"	O
Classic	O
"	O
that	O
now	O
signifies	O
the	O
historical	O
Mac	B-Application
OS	I-Application
as	O
a	O
whole	O
is	O
a	O
reference	O
to	O
the	O
Classic	O
Environment	O
,	O
a	O
compatibility	B-General_Concept
layer	I-General_Concept
that	O
helped	O
ease	O
the	O
transition	O
to	O
Mac	B-Application
OS	I-Application
X	I-Application
(	O
now	O
macOS	B-Application
)	O
.	O
</s>
<s>
macOS	B-Application
(	O
previously	O
Mac	O
OS	O
X	B-Operating_System
and	O
later	O
OS	O
X	B-Operating_System
)	O
is	O
a	O
series	O
of	O
proprietary	B-Application
graphical	B-Application
operating	B-General_Concept
systems	I-General_Concept
developed	O
and	O
marketed	O
by	O
Apple	O
Inc	O
.	O
since	O
2001	O
.	O
</s>
<s>
It	O
is	O
the	O
primary	O
operating	B-General_Concept
system	I-General_Concept
for	O
Apple	O
's	O
Mac	B-Device
computers	I-Device
.	O
</s>
<s>
Within	O
the	O
market	O
of	O
desktop	O
,	O
laptop	B-Device
and	O
home	O
computers	O
,	O
and	O
by	O
web	O
usage	O
,	O
it	O
is	O
the	O
second	O
most	O
widely	O
used	O
desktop	B-General_Concept
OS	I-General_Concept
,	O
after	O
Microsoft	B-Application
Windows	I-Application
.	O
</s>
<s>
macOS	B-Application
is	O
the	O
direct	O
successor	O
to	O
the	O
classic	B-Application
Mac	I-Application
OS	I-Application
,	O
the	O
line	O
of	O
Macintosh	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
with	O
nine	O
releases	O
from	O
1984	O
to	O
1999	O
.	O
macOS	B-Application
adopted	O
the	O
Unix	B-Application
kernel	B-Operating_System
and	O
inherited	O
technologies	O
developed	O
between	O
1985	O
and	O
1997	O
at	O
NeXT	O
,	O
the	O
company	O
that	O
Apple	O
co-founder	O
Steve	O
Jobs	O
created	O
after	O
leaving	O
Apple	O
in	O
1985	O
.	O
</s>
<s>
Releases	O
from	O
Mac	B-Application
OS	I-Application
X	I-Application
10.5	I-Application
Leopard	I-Application
and	O
thereafter	O
are	O
UNIX	B-Application
03	O
certified	O
.	O
</s>
<s>
Apple	O
's	O
mobile	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
,	O
iOS	B-Application
,	O
has	O
been	O
considered	O
a	O
variant	O
of	O
macOS	B-Application
.	O
</s>
<s>
Mac	B-Application
OS	I-Application
X	I-Application
10.0	O
(	O
code	O
named	O
Cheetah	O
)	O
was	O
the	O
first	O
major	O
release	O
and	O
version	O
of	O
macOS	B-Application
,	O
Apple	O
's	O
desktop	O
and	O
server	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
Mac	B-Application
OS	I-Application
X	I-Application
10.0	O
was	O
released	O
on	O
24	O
March	O
2001	O
for	O
a	O
price	O
of	O
US$129	O
.	O
</s>
<s>
It	O
was	O
the	O
successor	O
of	O
the	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
Public	I-Operating_System
Beta	I-Operating_System
and	O
the	O
predecessor	O
of	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
10.1	I-Operating_System
(	O
code	O
named	O
Puma	O
)	O
.	O
</s>
<s>
Mac	B-Application
OS	I-Application
X	I-Application
10.0	O
was	O
a	O
radical	O
departure	O
from	O
the	O
classic	B-Application
Mac	I-Application
OS	I-Application
and	O
was	O
Apple	O
's	O
long-awaited	O
answer	O
for	O
a	O
next	O
generation	O
Macintosh	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
.	O
</s>
<s>
It	O
introduced	O
a	O
brand	O
new	O
code	B-General_Concept
base	I-General_Concept
completely	O
separate	O
from	O
Mac	B-Operating_System
OS	I-Operating_System
9	I-Operating_System
's	O
as	O
well	O
as	O
all	O
previous	O
Apple	O
operating	B-General_Concept
systems	I-General_Concept
,	O
and	O
had	O
a	O
new	O
Unix-like	B-Operating_System
core	O
,	O
Darwin	B-Operating_System
,	O
which	O
features	O
a	O
new	O
memory	B-General_Concept
management	I-General_Concept
system	O
.	O
</s>
<s>
Unlike	O
releases	O
of	O
Mac	B-Application
OS	I-Application
X	I-Application
10.2	O
to	O
10.8	O
,	O
the	O
operating	B-General_Concept
system	I-General_Concept
was	O
not	O
externally	O
marketed	O
with	O
the	O
name	O
of	O
a	O
big	O
cat	O
.	O
</s>
<s>
The	O
Finder	B-Application
is	O
a	O
file	O
browser	O
allowing	O
quick	O
access	O
to	O
all	O
areas	O
of	O
the	O
computer	O
,	O
which	O
has	O
been	O
modified	O
throughout	O
subsequent	O
releases	O
of	O
macOS	B-Application
.	O
</s>
<s>
Quick	B-Operating_System
Look	I-Operating_System
has	O
been	O
part	O
of	O
the	O
Finder	B-Application
since	O
version	B-Application
10.5	I-Application
.	O
</s>
<s>
It	O
allows	O
for	O
dynamic	O
previews	O
of	O
files	O
,	O
including	O
videos	O
and	O
multi-page	O
documents	O
without	O
opening	O
any	O
other	O
applications	B-Application
.	O
</s>
<s>
Spotlight	B-Application
,	O
a	O
file	O
searching	O
technology	O
which	O
has	O
been	O
integrated	O
into	O
the	O
Finder	B-Application
since	O
version	B-Application
10.4	I-Application
,	O
allows	O
rapid	O
real-time	O
searches	O
of	O
data	O
files	O
;	O
mail	O
messages	O
;	O
photos	O
;	O
and	O
other	O
information	O
based	O
on	O
item	O
properties	O
(	O
metadata	O
)	O
and/or	O
content	O
.	O
</s>
<s>
macOS	B-Application
makes	O
use	O
of	O
a	O
Dock	O
,	O
which	O
holds	O
file	O
and	O
folder	O
shortcuts	O
as	O
well	O
as	O
minimized	O
windows	O
.	O
</s>
<s>
Apple	O
added	O
Exposé	O
in	O
version	B-Operating_System
10.3	I-Operating_System
(	O
called	O
Mission	O
Control	O
since	O
version	B-Application
10.7	I-Application
)	O
,	O
a	O
feature	O
which	O
includes	O
three	O
functions	O
to	O
help	O
accessibility	O
between	O
windows	O
and	O
desktop	O
.	O
</s>
<s>
FileVault	O
is	O
optional	O
encryption	O
of	O
the	O
user	O
's	O
files	O
with	O
the	O
128-bit	O
Advanced	B-Algorithm
Encryption	I-Algorithm
Standard	I-Algorithm
(	O
AES-128	B-Algorithm
)	O
.	O
</s>
<s>
Features	O
introduced	O
in	O
version	B-Application
10.4	I-Application
include	O
Automator	O
,	O
an	O
application	O
designed	O
to	O
create	O
an	O
automatic	O
workflow	O
for	O
different	O
tasks	O
;	O
Dashboard	B-Application
,	O
a	O
full-screen	O
group	O
of	O
small	O
applications	B-Application
called	O
desktop	O
widgets	O
that	O
can	O
be	O
called	O
up	O
and	O
dismissed	O
in	O
one	O
keystroke	O
;	O
and	O
Front	B-Operating_System
Row	I-Operating_System
,	O
a	O
media	O
viewer	O
interface	O
accessed	O
by	O
the	O
Apple	B-Operating_System
Remote	I-Operating_System
.	O
</s>
<s>
Sync	O
Services	B-Operating_System
allows	O
applications	B-Application
to	O
access	O
a	O
centralized	O
extensible	O
database	O
for	O
various	O
elements	O
of	O
user	O
data	O
,	O
including	O
calendar	O
and	O
contact	O
items	O
.	O
</s>
<s>
The	O
operating	B-General_Concept
system	I-General_Concept
then	O
managed	O
conflicting	O
edits	O
and	O
data	O
consistency	O
.	O
</s>
<s>
All	O
system	O
icons	O
are	O
scalable	O
up	O
to	O
512×512	O
pixels	O
as	O
of	O
version	B-Application
10.5	I-Application
to	O
accommodate	O
various	O
places	O
where	O
they	O
appear	O
in	O
larger	O
size	O
,	O
including	O
for	O
example	O
the	O
Cover	O
Flow	O
view	O
,	O
a	O
three-dimensional	O
graphical	B-Application
user	I-Application
interface	I-Application
included	O
with	O
iTunes	B-Operating_System
,	O
the	O
Finder	B-Application
,	O
and	O
other	O
Apple	O
products	O
for	O
visually	O
skimming	O
through	O
files	O
and	O
digital	O
media	O
libraries	B-Library
via	O
cover	O
artwork	O
.	O
</s>
<s>
That	O
version	O
also	O
introduced	O
Spaces	O
,	O
a	O
virtual	B-Application
desktop	I-Application
implementation	O
which	O
enables	O
the	O
user	O
to	O
have	O
more	O
than	O
one	O
desktop	O
and	O
display	O
them	O
in	O
an	O
Exposé-like	O
interface	O
;	O
an	O
automatic	O
backup	O
technology	O
called	O
Time	B-Operating_System
Machine	I-Operating_System
,	O
which	O
allows	O
users	O
to	O
view	O
and	O
restore	O
previous	O
versions	O
of	O
files	O
and	O
application	O
data	O
;	O
and	O
Screen	O
Sharing	O
was	O
built	O
in	O
for	O
the	O
first	O
time	O
.	O
</s>
<s>
In	O
more	O
recent	O
releases	O
,	O
Apple	O
has	O
developed	O
support	O
for	O
emoji	B-Application
characters	O
by	O
including	O
the	O
proprietary	B-Application
Apple	B-Protocol
Color	I-Protocol
Emoji	I-Protocol
font	O
.	O
</s>
<s>
Apple	O
has	O
also	O
connected	O
macOS	B-Application
with	O
social	O
networks	O
such	O
as	O
Twitter	O
and	O
Facebook	O
through	O
the	O
addition	O
of	O
share	O
buttons	O
for	O
content	O
such	O
as	O
pictures	O
and	O
text	O
.	O
</s>
<s>
Apple	O
has	O
brought	O
several	O
applications	B-Application
and	O
features	O
that	O
originally	O
debuted	O
in	O
iOS	B-Application
,	O
its	O
mobile	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
,	O
to	O
macOS	B-Application
in	O
recent	O
releases	O
,	O
notably	O
the	O
intelligent	B-Protocol
personal	I-Protocol
assistant	I-Protocol
Siri	B-Application
,	O
which	O
was	O
introduced	O
in	O
version	B-Operating_System
10.12	I-Operating_System
of	O
macOS	B-Application
.	O
</s>
<s>
Unix	B-Application
(	O
;	O
trademarked	O
as	O
UNIX	B-Application
)	O
is	O
a	O
family	O
of	O
multitasking	B-Operating_System
,	O
multiuser	B-Operating_System
computer	B-General_Concept
operating	I-General_Concept
systems	I-General_Concept
that	O
derive	O
from	O
the	O
original	O
AT&T	O
Unix	B-Application
,	O
whose	O
development	O
started	O
in	O
the	O
1970s	O
at	O
the	O
Bell	O
Labs	O
research	O
center	O
by	O
Ken	O
Thompson	O
,	O
Dennis	O
Ritchie	O
,	O
and	O
others	O
.	O
</s>
<s>
Initially	O
intended	O
for	O
use	O
inside	O
the	O
Bell	O
System	O
,	O
AT&T	O
licensed	O
Unix	B-Application
to	O
outside	O
parties	O
in	O
the	O
late	O
1970s	O
,	O
leading	O
to	O
a	O
variety	O
of	O
both	O
academic	O
and	O
commercial	O
Unix	B-Application
variants	O
from	O
vendors	O
including	O
University	O
of	O
California	O
,	O
Berkeley	O
(	O
BSD	B-Operating_System
)	O
,	O
Microsoft	O
(	O
Xenix	B-Application
)	O
,	O
Sun	O
Microsystems	O
(	O
SunOS/Solaris	O
)	O
,	O
HP/HPE	O
(	O
HP-UX	B-Application
)	O
,	O
and	O
IBM	O
(	O
AIX	B-Application
)	O
.	O
</s>
<s>
In	O
the	O
early	O
1990s	O
,	O
AT&T	O
sold	O
its	O
rights	O
in	O
Unix	B-Application
to	O
Novell	O
,	O
which	O
then	O
sold	O
its	O
Unix	B-Application
business	O
to	O
the	O
Santa	O
Cruz	O
Operation	O
(	O
SCO	O
)	O
in	O
1995	O
.	O
</s>
<s>
The	O
UNIX	B-Application
trademark	O
passed	O
to	O
The	B-Application
Open	I-Application
Group	I-Application
,	O
an	O
industry	O
consortium	O
founded	O
in	O
1996	O
,	O
which	O
allows	O
the	O
use	O
of	O
the	O
mark	O
for	O
certified	O
operating	B-General_Concept
systems	I-General_Concept
that	O
comply	O
with	O
the	O
Single	O
UNIX	B-Application
Specification	O
(	O
SUS	O
)	O
.	O
</s>
<s>
However	O
,	O
Novell	O
continues	O
to	O
own	O
the	O
Unix	B-Application
copyrights	O
,	O
which	O
the	O
SCO	O
Group	O
,	O
Inc	O
.	O
v	O
.	O
Novell	O
,	O
Inc	O
.	O
court	O
case	O
(	O
2010	O
)	O
confirmed	O
.	O
</s>
<s>
Unix	B-Application
systems	I-Application
are	O
characterized	O
by	O
a	O
modular	O
design	O
that	O
is	O
sometimes	O
called	O
the	O
"	O
Unix	B-Operating_System
philosophy	I-Operating_System
"	O
.	O
</s>
<s>
According	O
to	O
this	O
philosophy	O
,	O
the	O
operating	B-General_Concept
system	I-General_Concept
should	O
provide	O
a	O
set	O
of	O
simple	O
tools	O
,	O
each	O
of	O
which	O
performs	O
a	O
limited	O
,	O
well-defined	O
function	O
.	O
</s>
<s>
A	O
unified	O
filesystem	B-Application
(	O
the	O
Unix	B-Application
filesystem	I-Application
)	O
and	O
an	O
inter-process	B-Operating_System
communication	I-Operating_System
mechanism	O
known	O
as	O
"	O
pipes	B-Operating_System
"	O
serve	O
as	O
the	O
main	O
means	O
of	O
communication	O
,	O
and	O
a	O
shell	B-Operating_System
scripting	O
and	O
command	O
language	O
(	O
the	O
Unix	B-Application
shell	I-Application
)	O
is	O
used	O
to	O
combine	O
the	O
tools	O
to	O
perform	O
complex	O
workflows	O
.	O
</s>
<s>
Unix	B-Application
distinguishes	O
itself	O
from	O
its	O
predecessors	O
as	O
the	O
first	O
portable	B-Architecture
operating	B-General_Concept
system	I-General_Concept
:	O
almost	O
the	O
entire	O
operating	B-General_Concept
system	I-General_Concept
is	O
written	O
in	O
the	O
C	B-Language
programming	I-Language
language	I-Language
,	O
which	O
allows	O
Unix	B-Application
to	O
operate	O
on	O
numerous	O
platforms	O
.	O
</s>
<s>
macOS	B-Application
,	O
described	O
above	O
,	O
is	O
a	O
Unix-like	B-Operating_System
system	I-Operating_System
,	O
and	O
,	O
beginning	O
with	O
Mac	B-Application
OS	I-Application
X	I-Application
Leopard	I-Application
,	O
is	O
certified	O
to	O
comply	O
with	O
the	O
SUS	O
.	O
</s>
<s>
Linux	B-Application
is	O
a	O
family	O
of	O
open-source	B-Application
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
based	O
on	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
,	O
an	O
operating	B-Operating_System
system	I-Operating_System
kernel	I-Operating_System
first	O
released	O
on	O
17	O
September	O
1991	O
,	O
by	O
Linus	O
Torvalds	O
.	O
</s>
<s>
Linux	B-Application
is	O
typically	O
packaged	B-Application
in	O
a	O
Linux	B-Application
distribution	I-Application
.	O
</s>
<s>
Distributions	O
include	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
and	O
supporting	O
system	B-Application
software	I-Application
and	O
libraries	B-Library
,	O
many	O
of	O
which	O
are	O
provided	O
by	O
the	B-Application
GNU	I-Application
Project	I-Application
.	O
</s>
<s>
Many	O
Linux	B-Application
distributions	I-Application
use	O
the	O
word	O
"	O
Linux	B-Application
"	O
in	O
their	O
name	O
,	O
but	O
the	B-Operating_System
Free	I-Operating_System
Software	I-Operating_System
Foundation	I-Operating_System
uses	O
the	O
name	O
"	O
GNU/Linux	B-Application
"	O
to	O
emphasize	O
the	O
importance	O
of	O
GNU	B-Operating_System
software	B-Application
,	O
causing	B-Application
some	I-Application
controversy	I-Application
.	O
</s>
<s>
Popular	O
Linux	B-Application
distributions	I-Application
include	O
Debian	O
,	O
Fedora	O
,	O
and	O
Ubuntu	B-Operating_System
.	O
</s>
<s>
Commercial	O
distributions	O
include	O
Red	O
Hat	O
Enterprise	O
Linux	B-Application
and	O
SUSE	O
Linux	B-Application
Enterprise	B-Application
Server	I-Application
.	O
</s>
<s>
Desktop	O
Linux	B-Application
distributions	I-Application
include	O
a	O
windowing	B-Application
system	I-Application
such	O
as	O
X11	B-Operating_System
or	O
Wayland	B-Language
,	O
and	O
a	O
desktop	O
environment	O
such	O
as	O
GNOME	B-Application
or	O
KDE	B-Language
Plasma	I-Language
.	O
</s>
<s>
Distributions	O
intended	O
for	O
servers	B-Application
may	O
omit	O
graphics	O
altogether	O
,	O
or	O
include	O
a	O
solution	B-Application
stack	I-Application
such	O
as	O
LAMP	B-Application
.	O
</s>
<s>
Because	O
Linux	B-Application
is	O
freely	O
redistributable	O
,	O
anyone	O
may	O
create	O
a	O
distribution	O
for	O
any	O
purpose	O
.	O
</s>
<s>
Linux	B-Application
was	O
originally	O
developed	O
for	O
personal	O
computers	O
based	O
on	O
the	O
Intel	B-Operating_System
x86	I-Operating_System
architecture	O
,	O
but	O
has	O
since	O
been	O
ported	O
to	O
more	O
platforms	O
than	O
any	O
other	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
Because	O
of	O
the	O
dominance	O
of	O
the	O
Linux-based	O
Android	B-Application
on	O
smartphones	B-Application
,	O
,	O
Linux	B-Application
also	O
has	O
the	O
largest	B-Operating_System
installed	B-Operating_System
base	I-Operating_System
of	O
all	O
general-purpose	B-General_Concept
operating	I-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
Although	O
it	O
is	O
,	O
,	O
used	O
by	O
only	O
around	O
2.9	O
percent	O
of	O
desktop	B-Device
computers	I-Device
,	O
the	O
Chromebook	B-Operating_System
,	O
which	O
runs	O
the	O
Linux	O
kernel-based	O
ChromeOS	B-Operating_System
,	O
dominates	O
the	O
US	O
K	O
–	O
12	O
education	O
market	O
and	O
represents	O
nearly	O
20	O
percent	O
of	O
sub-	O
$300	O
notebook	B-Device
sales	O
in	O
the	O
US	O
.	O
</s>
<s>
Linux	B-Application
is	O
the	O
leading	O
operating	B-General_Concept
system	I-General_Concept
on	O
servers	B-Application
(	O
over	O
96.4	O
%	O
of	O
the	O
top	O
1million	O
web	B-Application
servers	I-Application
 '	O
operating	B-General_Concept
systems	I-General_Concept
are	O
Linux	B-Application
)	O
,	O
leads	O
other	O
large	O
systems	O
such	O
as	O
mainframe	B-Architecture
computers	I-Architecture
,	O
and	O
is	O
the	O
only	O
OS	O
used	O
on	O
TOP500	B-Operating_System
supercomputers	B-Architecture
(	O
since	O
November	O
2017	O
,	O
having	O
gradually	O
eliminated	O
all	O
competitors	O
)	O
.	O
</s>
<s>
Linux	B-Application
also	O
runs	O
on	O
embedded	B-Architecture
systems	I-Architecture
,	O
i.e.	O
</s>
<s>
devices	O
whose	O
operating	B-General_Concept
system	I-General_Concept
is	O
typically	O
built	O
into	O
the	O
firmware	B-Application
and	O
is	O
highly	O
tailored	O
to	O
the	O
system	O
.	O
</s>
<s>
This	O
includes	O
routers	B-Protocol
,	O
automation	B-Application
controls	O
,	O
smart	O
home	O
technology	O
(	O
such	O
as	O
Google	B-Application
Nest	I-Application
)	O
,	O
televisions	O
(	O
Samsung	O
and	O
LG	O
Smart	B-Device
TVs	I-Device
use	O
Tizen	B-Application
and	O
WebOS	B-Operating_System
,	O
respectively	O
)	O
,	O
automobiles	O
(	O
for	O
example	O
,	O
Tesla	O
,	O
Audi	O
,	O
Mercedes-Benz	O
,	O
Hyundai	O
,	O
and	O
Toyota	O
all	O
rely	O
on	O
Linux	B-Application
)	O
,	O
digital	B-Application
video	I-Application
recorders	I-Application
,	O
video	B-Device
game	I-Device
consoles	I-Device
,	O
and	O
smartwatches	B-Application
.	O
</s>
<s>
The	O
Falcon	O
9	O
's	O
and	O
the	O
Dragon	O
2	O
's	O
avionics	O
use	O
a	O
customized	O
version	O
of	O
Linux	B-Application
.	O
</s>
<s>
Linux	B-Application
is	O
one	O
of	O
the	O
most	O
prominent	O
examples	O
of	O
free	B-License
and	I-License
open-source	I-License
software	I-License
collaboration	O
.	O
</s>
<s>
The	O
source	O
code	O
may	O
be	O
used	O
,	O
modified	O
and	O
distributed	O
commercially	O
or	O
non-commercially	O
by	O
anyone	O
under	O
the	O
terms	O
of	O
its	O
respective	O
licenses	O
,	O
such	O
as	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
90%	O
of	O
all	O
cloud	B-Architecture
infrastructure	O
is	O
powered	O
by	O
Linux	B-Application
including	O
supercomputers	B-Architecture
and	O
cloud	B-Architecture
providers	O
.	O
</s>
<s>
74%	O
of	O
smartphones	B-Application
in	O
the	O
world	O
are	O
Linux-based	O
.	O
</s>
<s>
KDE	B-Language
Plasma	I-Language
5	I-Language
is	O
the	O
fifth	O
and	O
current	O
generation	O
of	O
the	O
graphical	B-Application
workspaces	B-Application
environment	O
created	O
by	O
KDE	B-Application
primarily	O
for	O
Linux	B-Application
systems	O
.	O
</s>
<s>
KDE	B-Language
Plasma	I-Language
5	I-Language
is	O
the	O
successor	O
of	O
KDE	B-Language
Plasma	I-Language
4	I-Language
and	O
was	O
first	O
released	O
on	O
15	O
July	O
2014	O
.	O
</s>
<s>
The	O
graphical	B-Application
interface	I-Application
was	O
fully	O
migrated	O
to	O
QML	B-Language
,	O
which	O
uses	O
OpenGL	B-Application
for	O
hardware	O
acceleration	O
,	O
which	O
resulted	O
in	O
better	O
performance	O
and	O
reduced	O
power	O
consumption	O
.	O
</s>
<s>
FreeBSD	B-Operating_System
is	O
a	O
free	B-License
and	I-License
open-source	I-License
Unix-like	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
descended	O
from	O
the	O
Berkeley	B-Operating_System
Software	I-Operating_System
Distribution	I-Operating_System
(	O
BSD	B-Operating_System
)	O
,	O
which	O
was	O
based	O
on	O
Research	B-Operating_System
Unix	I-Operating_System
.	O
</s>
<s>
The	O
first	O
version	O
of	O
FreeBSD	B-Operating_System
was	O
released	O
in	O
1993	O
.	O
</s>
<s>
In	O
2005	O
,	O
FreeBSD	B-Operating_System
was	O
the	O
most	O
popular	O
open-source	B-Application
BSD	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
,	O
accounting	O
for	O
more	O
than	O
three-quarters	O
of	O
all	O
installed	O
simply	B-Operating_System
,	I-Operating_System
permissively	I-Operating_System
licensed	I-Operating_System
BSD	B-Operating_System
systems	O
.	O
</s>
<s>
FreeBSD	B-Operating_System
has	O
similarities	O
with	O
Linux	B-Application
,	O
with	O
two	O
major	O
differences	O
in	O
scope	O
and	O
licensing	O
.	O
</s>
<s>
First	O
,	O
FreeBSD	B-Operating_System
maintains	O
a	O
complete	O
system	O
,	O
i.e.	O
</s>
<s>
the	O
project	O
delivers	O
a	O
kernel	B-Operating_System
,	O
device	B-Application
drivers	I-Application
,	O
userland	O
utilities	O
,	O
and	O
documentation	O
,	O
as	O
opposed	O
to	O
Linux	B-Application
only	O
delivering	O
a	O
kernel	B-Operating_System
and	O
drivers	O
,	O
and	O
relying	O
on	O
third-parties	O
for	O
system	B-Application
software	I-Application
.	O
</s>
<s>
Second	O
,	O
FreeBSD	B-Operating_System
source	O
code	O
is	O
generally	O
released	O
under	O
a	O
permissive	B-License
BSD	B-Operating_System
license	I-Operating_System
,	O
as	O
opposed	O
to	O
the	O
copyleft	B-License
GPL	B-License
used	O
by	O
Linux	B-Application
.	O
</s>
<s>
The	O
FreeBSD	B-Operating_System
project	I-Operating_System
includes	O
a	O
security	O
team	O
overseeing	O
all	O
software	B-Application
shipped	O
in	O
the	O
base	O
distribution	O
.	O
</s>
<s>
A	O
wide	O
range	O
of	O
additional	O
third-party	O
applications	B-Application
may	O
be	O
installed	O
using	O
the	O
pkg	O
package	B-Application
management	I-Application
system	I-Application
or	O
FreeBSD	B-Application
Ports	I-Application
,	O
or	O
by	O
compiling	B-Language
source	O
code	O
.	O
</s>
<s>
Much	O
of	O
FreeBSD	B-Operating_System
's	O
codebase	B-General_Concept
has	O
become	O
an	O
integral	O
part	O
of	O
other	O
operating	B-General_Concept
systems	I-General_Concept
such	O
as	O
Darwin	B-Operating_System
(	O
the	O
basis	O
for	O
macOS	B-Application
,	O
iOS	B-Application
,	O
iPadOS	B-Operating_System
,	O
watchOS	B-Device
,	O
and	O
tvOS	B-Operating_System
)	O
,	O
TrueNAS	B-Application
(	O
an	O
open-source	B-Application
NAS/SAN	O
operating	B-General_Concept
system	I-General_Concept
)	O
,	O
and	O
the	O
system	B-Application
software	I-Application
for	O
the	O
PlayStation	B-Operating_System
3	I-Operating_System
and	O
PlayStation	B-Operating_System
4	I-Operating_System
game	O
consoles	O
.	O
</s>
<s>
ChromeOS	B-Operating_System
(	O
formerly	O
Chrome	B-Operating_System
OS	I-Operating_System
,	O
sometimes	O
styled	O
as	O
chromeOS	B-Operating_System
)	O
is	O
a	O
Gentoo	O
Linux-based	O
operating	B-General_Concept
system	I-General_Concept
designed	O
by	O
Google	O
.	O
</s>
<s>
It	O
is	O
derived	O
from	O
the	O
free	B-Application
software	I-Application
ChromiumOS	B-Application
and	O
uses	O
the	O
Google	B-Application
Chrome	I-Application
web	O
browser	O
as	O
its	O
principal	O
user	B-Application
interface	I-Application
.	O
</s>
<s>
However	O
,	O
ChromeOS	B-Operating_System
is	O
proprietary	B-Application
software	I-Application
.	O
</s>
<s>
Google	O
announced	O
the	O
project	O
in	O
July	O
2009	O
,	O
conceiving	O
it	O
as	O
an	O
operating	B-General_Concept
system	I-General_Concept
in	O
which	O
both	O
applications	B-Application
and	O
user	O
data	O
reside	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
:	O
hence	O
ChromeOS	B-Operating_System
primarily	O
runs	O
web	B-Application
applications	I-Application
.	O
</s>
<s>
The	O
first	O
ChromeOS	B-Operating_System
laptop	B-Device
,	O
known	O
as	O
a	O
Chromebook	B-Operating_System
,	O
arrived	O
in	O
May	O
2011	O
.	O
</s>
<s>
Initial	O
Chromebook	B-Operating_System
shipments	O
from	O
Samsung	O
and	O
Acer	O
occurred	O
in	O
July	O
2011	O
.	O
</s>
<s>
ChromeOS	B-Operating_System
has	O
an	O
integrated	O
media	O
player	O
and	O
file	B-Application
manager	I-Application
.	O
</s>
<s>
It	O
supports	O
Chrome	B-Operating_System
Apps	I-Operating_System
,	O
which	O
resemble	O
native	O
applications	B-Application
,	O
as	O
well	O
as	O
remote	B-Protocol
access	I-Protocol
to	O
the	O
desktop	O
.	O
</s>
<s>
Reception	O
was	O
initially	O
skeptical	O
,	O
with	O
some	O
observers	O
arguing	O
that	O
a	O
browser	O
running	O
on	O
any	O
operating	B-General_Concept
system	I-General_Concept
was	O
functionally	O
equivalent	O
.	O
</s>
<s>
As	O
more	O
ChromeOS	B-Operating_System
machines	O
have	O
entered	O
the	O
market	O
,	O
the	O
operating	B-General_Concept
system	I-General_Concept
is	O
now	O
seldom	O
evaluated	O
apart	O
from	O
the	O
hardware	O
that	O
runs	O
it	O
.	O
</s>
<s>
Android	B-Application
applications	I-Application
started	O
to	O
become	O
available	O
for	O
the	O
operating	B-General_Concept
system	I-General_Concept
in	O
2014	O
,	O
and	O
in	O
2016	O
,	O
access	O
to	O
Android	B-Application
apps	O
in	O
Google	B-Application
Play	I-Application
's	O
entirety	O
was	O
introduced	O
on	O
supported	O
ChromeOS	B-Operating_System
devices	O
.	O
</s>
<s>
Support	O
for	O
a	O
Linux	B-Application
terminal	O
and	O
applications	B-Application
,	O
known	O
as	O
Project	O
Crostini	O
,	O
was	O
released	O
to	O
the	O
stable	O
channel	O
in	O
ChromeOS	B-Operating_System
69	O
.	O
</s>
<s>
This	O
was	O
made	O
possible	O
via	O
a	O
lightweight	B-Operating_System
Linux	I-Operating_System
kernel	B-Operating_System
that	O
runs	O
containers	O
inside	O
a	O
virtual	B-Architecture
machine	I-Architecture
.	O
</s>
<s>
ChromeOS	B-Operating_System
is	O
only	O
available	O
pre-installed	O
on	O
hardware	O
from	O
Google	O
manufacturing	O
partners	O
,	O
but	O
there	O
are	O
unofficial	O
methods	O
that	O
allow	O
it	O
to	O
be	O
installed	O
in	O
other	O
equipment	O
.	O
</s>
<s>
Its	O
open-source	B-Application
upstream	O
,	O
ChromiumOS	B-Application
,	O
can	O
be	O
compiled	B-Language
from	O
downloaded	O
source	O
code	O
.	O
</s>
<s>
Early	O
on	O
,	O
Google	O
provided	O
design	O
goals	O
for	O
ChromeOS	B-Operating_System
,	O
but	O
has	O
not	O
otherwise	O
released	O
a	O
technical	O
description	O
.	O
</s>
