<s>
RetroArch	B-Application
is	O
a	O
free	B-License
and	I-License
open-source	I-License
,	O
cross-platform	B-Operating_System
frontend	B-Architecture
for	O
emulators	B-Application
,	O
game	O
engines	O
,	O
video	O
games	O
,	O
media	B-Application
players	I-Application
and	O
other	O
applications	O
.	O
</s>
<s>
It	O
is	O
the	O
reference	O
implementation	O
of	O
the	O
libretro	B-Application
API	B-Application
,	O
designed	O
to	O
be	O
fast	O
,	O
lightweight	O
,	O
portable	O
and	O
without	O
dependencies	O
.	O
</s>
<s>
It	O
is	O
licensed	O
under	O
the	O
GNU	O
GPLv3	B-License
.	O
</s>
<s>
RetroArch	B-Application
runs	O
programs	O
converted	O
into	O
dynamic	O
libraries	O
called	O
libretro	B-Application
cores	O
,	O
using	O
several	O
user	B-Application
interfaces	I-Application
such	O
as	O
command-line	B-Application
interface	I-Application
,	O
a	O
few	O
graphical	B-Application
user	I-Application
interfaces	I-Application
(	O
GUI	B-Application
)	O
optimized	O
for	O
gamepads	B-Device
(	O
the	O
most	O
famous	O
one	O
being	O
called	O
XMB	B-Device
,	O
a	O
clone	O
of	O
Sony	O
's	O
XMB	B-Device
)	O
,	O
several	O
input	O
,	O
audio	O
and	O
video	O
drivers	O
,	O
plus	O
other	O
sophisticated	O
features	O
like	O
dynamic	O
rate	O
control	O
,	O
audio	O
filters	O
,	O
multi-pass	O
shaders	O
,	O
netplay	O
,	O
gameplay	O
rewinding	O
,	O
cheats	O
,	O
etc	O
.	O
</s>
<s>
RetroArch	B-Application
has	O
been	O
ported	O
to	O
many	O
platforms	O
.	O
</s>
<s>
It	O
can	O
run	O
on	O
several	O
PC	O
operating	B-General_Concept
systems	I-General_Concept
(	O
Windows	B-Application
,	O
macOS	B-Application
,	O
Linux	B-Application
)	O
,	O
home	O
consoles	O
(	O
PlayStation	B-Operating_System
4	I-Operating_System
,	O
Xbox	B-Device
Series	I-Device
X	I-Device
,	O
Wii	B-Device
U	I-Device
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
handheld	O
consoles	O
(	O
PlayStation	B-Device
Vita	I-Device
,	O
Nintendo	B-Device
Switch	I-Device
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
on	O
smartphones	O
(	O
Android	B-Application
,	O
iOS	B-Application
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
single-board	O
computers	O
(	O
Raspberry	B-Operating_System
Pi	I-Operating_System
,	O
ODROID	B-Application
,	O
etc	O
.	O
)	O
</s>
<s>
and	O
even	O
on	O
web	O
browsers	O
by	O
using	O
the	O
Emscripten	B-Language
compiler	O
.	O
</s>
<s>
Formerly	O
known	O
as	O
SSNES	O
,	O
initially	O
based	O
on	O
pseudonymous	O
programmer	O
Near	O
's	O
libretro	B-Application
predecessor	O
libsnes	O
,	O
it	O
began	O
its	O
development	O
in	O
2010	O
with	O
Hans-Kristian	O
"	O
themaister	O
"	O
Arntzen	O
committing	O
the	O
first	O
change	O
on	O
GitHub	B-Application
.	O
</s>
<s>
It	O
was	O
intended	O
as	O
a	O
replacement	O
to	O
bsnes	B-Language
's	O
Qt-based	O
interface	B-Application
but	O
it	O
grew	O
to	O
support	O
more	O
emulation	B-Application
"	O
cores	O
"	O
.	O
</s>
<s>
On	O
April	O
21	O
,	O
2012	O
,	O
SSNES	O
was	O
officially	O
renamed	O
to	O
RetroArch	B-Application
to	O
reflect	O
this	O
change	O
in	O
direction	O
.	O
</s>
<s>
RetroArch	B-Application
's	O
version	O
1.0.0.0	O
was	O
released	O
on	O
January	O
11	O
,	O
2014	O
,	O
and	O
at	O
the	O
time	O
was	O
available	O
on	O
seven	O
distinct	O
platforms	O
.	O
</s>
<s>
On	O
February	O
16	O
,	O
2016	O
,	O
RetroArch	B-Application
became	O
one	O
of	O
the	O
first	O
ever	O
applications	O
to	O
implement	O
support	O
for	O
the	O
Vulkan	B-Application
graphics	I-Application
API	I-Application
,	O
having	O
done	O
so	O
on	O
the	O
same	O
day	O
of	O
the	O
API	B-Application
's	O
official	O
release	O
day	O
.	O
</s>
<s>
On	O
November	O
27	O
,	O
2016	O
,	O
the	O
Libretro	B-Application
Team	O
announced	O
that	O
,	O
alongside	O
(	O
LibreELEC-based	O
RetroArch	B-Application
operating	B-General_Concept
system	I-General_Concept
)	O
,	O
RetroArch	B-Application
would	O
be	O
on	O
the	O
Patreon	O
crowdfunding	O
platform	O
to	O
allow	O
providing	O
bounties	O
for	O
developers	O
who	O
fix	O
specific	O
software	B-Error_Name
bugs	I-Error_Name
and	O
to	O
cover	O
the	O
costs	O
for	O
matchmaking	O
servers	O
.	O
</s>
<s>
In	O
December	O
2016	O
,	O
GoGames	O
–	O
a	O
company	O
contracted	O
by	O
video	O
game	O
developer	O
and	O
publisher	O
Sega	O
–	O
approached	O
the	O
RetroArch	B-Application
developers	O
with	O
the	O
intention	O
of	O
using	O
their	O
software	O
in	O
their	O
SEGA	O
Forever	O
project	O
but	O
ultimately	O
the	O
cooperation	O
did	O
not	O
come	O
to	O
fruition	O
due	O
to	O
licensing	O
disagreements	O
.	O
</s>
<s>
The	O
Libretro	B-Application
Team	O
planned	O
to	O
release	O
RetroArch	B-Application
onto	O
Steam	B-Application
as	O
a	O
free	O
download	O
,	O
integrating	O
Steamworks	O
features	O
into	O
the	O
platform	O
in	O
July	O
2019	O
.	O
</s>
<s>
It	O
would	O
have	O
been	O
the	O
first	O
major	O
dedicated	O
emulation	B-Application
title	O
to	O
be	O
released	O
on	O
the	O
platform	O
at	O
the	O
time	O
.	O
</s>
<s>
In	O
August	O
2020	O
,	O
someone	O
impersonating	O
a	O
trusted	O
member	O
of	O
the	O
team	O
got	O
access	O
to	O
the	O
buildbot	O
server	O
and	O
the	O
GitHub	B-Application
account	O
for	O
the	O
libretro	B-Application
organization	O
,	O
causing	O
vandalism	O
and	O
server	O
wipes	O
.	O
</s>
<s>
In	O
November	O
2020	O
,	O
RetroArch	B-Application
in	O
conjunction	O
with	O
a	O
PCSX2	B-Application
libretro	B-Application
core	O
allowed	O
the	O
Xbox	B-Device
Series	I-Device
X	I-Device
and	I-Device
Series	I-Device
S	I-Device
to	O
emulate	O
the	O
PlayStation	B-Device
2	I-Device
,	O
something	O
that	O
Sony	O
's	O
own	O
PlayStation	B-Device
5	I-Device
could	O
not	O
do	O
at	O
the	O
time	O
.	O
</s>
<s>
On	O
September	O
14	O
,	O
2021	O
,	O
RetroArch	B-Application
was	O
released	O
on	O
Steam	B-Application
.	O
</s>
<s>
Advanced	O
GPU	O
shader	O
support	O
-	O
A	O
multi-pass	O
post-processing	O
shader	O
pipeline	B-General_Concept
to	O
allow	O
efficient	O
usage	O
of	O
image	B-Algorithm
scaling	I-Algorithm
algorithms	O
,	O
emulation	B-Application
of	O
complex	O
CRT	B-Device
,	O
NTSC	O
video	O
artifacts	O
and	O
other	O
effects	O
;	O
</s>
<s>
FFmpeg	B-Library
recording	O
-	O
Built-in	O
support	O
for	O
lossless	B-Algorithm
video	O
recording	O
using	O
FFmpeg	B-Library
's	O
libavcodec	B-Language
;	O
</s>
<s>
Gamepad	B-Device
abstraction	B-Architecture
layer	I-Architecture
called	O
Retropad	O
;	O
</s>
<s>
Gamepad	B-Device
auto-configuration	O
-	O
Zero-input	O
needed	O
from	O
the	O
user	O
after	O
plugging	O
gamepads	B-Device
in	O
;	O
</s>
<s>
Peer-to-peer	O
netplay	O
that	O
uses	O
a	O
rollback	B-Application
technique	O
similar	O
to	O
GGPO	B-Application
;	O
</s>
<s>
Audio	O
DSP	B-Architecture
plugins	O
like	O
an	O
equalizer	O
,	O
reverb	O
and	O
other	O
effects	O
;	O
</s>
<s>
Button	O
overlays	O
for	O
touchscreen	B-Device
devices	O
like	O
smartphones	O
;	O
</s>
<s>
Automatically	O
build	O
categorized	O
playlists	O
by	O
scanning	O
directories	B-Application
for	O
games/ROMs	O
;	O
</s>
<s>
Multiple	O
interfaces	B-Application
including	O
:	O
CLI	B-Application
,	O
XMB	B-Device
(	O
optimized	O
for	O
gamepads	B-Device
)	O
,	O
GLUI/MaterialUI	O
(	O
optimized	O
for	O
touch	O
devices	O
)	O
,	O
RGUI	O
and	O
Ozone	O
(	O
available	O
everywhere	O
)	O
;	O
</s>
<s>
Game	B-General_Concept
ROM	I-General_Concept
scanner	O
-	O
Automatically	O
constructs	O
playlists	O
by	O
comparing	O
the	O
hashsums	B-Error_Name
of	O
a	O
directory	B-Application
's	O
files	O
against	O
databases	O
of	O
hashsums	B-Error_Name
of	O
known	O
good	O
game	O
copies	O
;	O
</s>
<s>
Libretro	B-Application
database	O
of	O
cores	O
,	O
games	O
,	O
cheats	O
,	O
etc	O
.	O
</s>
<s>
OpenGL	B-Application
and	O
Vulkan	B-Application
API	I-Application
support	O
;	O
</s>
<s>
Run-Ahead	O
-	O
Hide	O
the	O
input	O
lag	O
of	O
emulated	B-Application
systems	O
by	O
using	O
both	O
savestates	O
and	O
fast-forwarding	O
;	O
</s>
<s>
AI	O
Service	O
-	O
Uses	O
machine	B-Application
translation	I-Application
external	O
services	O
to	O
translate	O
game	O
text	O
on	O
screen	O
.	O
</s>
<s>
RetroArch	B-Application
can	O
run	O
any	O
libretro	B-Application
core	O
.	O
</s>
<s>
While	O
RetroArch	B-Application
is	O
available	O
for	O
many	O
platforms	O
,	O
the	O
availability	O
of	O
a	O
specific	O
core	O
varies	O
per	O
platform	O
.	O
</s>
<s>
Below	O
is	O
a	O
non-exhaustive	O
table	O
of	O
which	O
systems	O
are	O
available	O
to	O
RetroArch	B-Application
and	O
what	O
project	O
the	O
core	O
is	O
based	O
on	O
:	O
</s>
<s>
RetroArch	B-Application
has	O
been	O
praised	O
for	O
the	O
number	O
of	O
systems	O
and	O
games	O
it	O
can	O
play	O
under	O
a	O
single	O
interface	B-Application
.	O
</s>
<s>
On	O
Android	B-Application
,	O
it	O
has	O
been	O
praised	O
for	O
the	O
fact	O
that	O
overlays	O
can	O
be	O
customized	O
,	O
for	O
the	O
expandability	O
of	O
the	O
libretro	B-Application
cores	O
it	O
supports	O
,	O
for	O
its	O
compatibility	O
with	O
several	O
USB	O
and	O
Bluetooth	O
controller	O
peripherals	O
,	O
in	O
addition	O
to	O
the	O
app	O
being	O
free	O
and	O
having	O
no	O
ads	O
.	O
</s>
<s>
Tyler	O
Loch	O
,	O
writing	O
for	O
Ars	O
Technica	O
,	O
said	O
that	O
RetroArch	B-Application
's	O
'	O
Run-Ahead	O
'	O
feature	O
is	O
"	O
arguably	O
the	O
biggest	O
improvement	O
to	O
the	O
experience	O
the	O
retro	O
gaming	O
community	O
has	O
yet	O
seen	O
"	O
.	O
</s>
