<s>
PlayStation	B-Device
Portable	I-Device
homebrew	I-Device
refers	O
to	O
the	O
process	O
of	O
using	O
exploits	O
and	O
hacks	O
to	O
execute	O
unsigned	O
code	O
on	O
the	O
PlayStation	B-Operating_System
Portable	I-Operating_System
(	O
PSP	B-Operating_System
)	O
.	O
</s>
<s>
Additional	O
features	O
added	O
including	O
the	O
ability	O
to	O
emulate	O
and	O
play	O
the	O
ROMs	O
of	O
other	O
consoles	O
,	O
play	O
homebrew	B-Application
games	O
,	O
share	O
music	O
,	O
print	O
photos	O
,	O
watch	O
videos	O
from	O
streaming	O
sites	O
such	O
as	O
YouTube	O
,	O
and	O
run	O
additional	O
video	O
formats	O
originally	O
unsupported	O
by	O
the	O
device	O
.	O
</s>
<s>
Homebrew	B-Application
emulators	O
were	O
created	O
for	O
NES	B-Language
,	O
SNES	B-Application
,	O
Game	B-Device
Boy	I-Device
Color	I-Device
,	O
Game	B-Device
Boy	I-Device
Advance	I-Device
,	O
Sega	B-Operating_System
Genesis	I-Operating_System
and	O
Nintendo	B-Operating_System
64	I-Operating_System
console	O
systems	O
among	O
others	O
.	O
</s>
<s>
PlayStation	B-Device
1	I-Device
emulation	O
was	O
native	O
,	O
made	O
by	O
Sony	O
.	O
</s>
<s>
The	O
reverse	O
engineering	O
process	O
to	O
understand	O
the	O
PSP	B-Device
hardware	I-Device
started	O
shortly	O
after	O
the	O
advent	O
of	O
homebrew	B-Application
unsigned	O
code	O
execution	O
.	O
</s>
<s>
This	O
effort	O
led	O
to	O
development	O
of	O
Toolchain	B-General_Concept
and	O
SDK	B-Application
by	O
enthusiasts	O
and	O
paved	O
the	O
way	O
to	O
utilise	O
vector	B-Operating_System
floating	I-Operating_System
point	I-Operating_System
co-processor	I-Operating_System
,	O
GPU	B-Architecture
and	O
audio	O
capabilities	O
of	O
the	O
device	O
without	O
asking	O
Sony	O
for	O
permission	O
.	O
</s>
<s>
Several	O
demoscene	O
non-interactive	O
creations	O
were	O
released	O
targeting	O
PSP	B-Operating_System
such	O
as	O
Suicide	O
Barbie	O
,	O
purely	O
to	O
demonstrate	O
optimisation	O
skills	O
of	O
the	O
developers	O
and	O
the	O
power	O
of	O
the	O
handheld	O
.	O
</s>
<s>
Soon	O
after	O
the	O
PSP	B-Operating_System
was	O
released	O
,	O
hackers	O
began	O
to	O
discover	O
exploits	O
in	O
the	O
PSP	B-Operating_System
that	O
could	O
be	O
used	O
to	O
run	O
unsigned	O
code	O
on	O
the	O
device	O
.	O
</s>
<s>
Sony	O
released	O
version	O
1.51	O
of	O
the	O
PSP	B-Operating_System
firmware	I-Operating_System
in	O
May	O
2005	O
to	O
plug	O
the	O
holes	O
that	O
hackers	O
were	O
using	O
to	O
gain	O
access	O
to	O
the	O
device	O
.	O
</s>
<s>
On	O
15	O
June	O
2005	O
the	O
hackers	O
distributed	O
the	O
cracked	B-Application
code	O
of	O
the	O
PSP	B-Operating_System
on	O
the	O
internet	O
.	O
</s>
<s>
Hackers	O
refused	O
to	O
apply	O
updates	O
which	O
would	O
render	O
their	O
hacks	O
unusable	O
so	O
Sony	O
attempted	O
to	O
convince	O
users	O
that	O
there	O
was	O
a	O
benefit	O
to	O
upgrading	O
by	O
including	O
new	O
features	O
in	O
the	O
firmware	O
updates	O
,	O
such	O
as	O
a	O
web	B-Application
browser	I-Application
,	O
and	O
not	O
just	O
security	O
patches	O
to	O
plug	O
the	O
vulnerabilities	O
.	O
</s>
<s>
In	O
August	O
2005	O
Sony	O
released	O
version	O
2.0	O
of	O
the	O
firmware	O
which	O
included	O
the	O
web	B-Application
browser	I-Application
,	O
file	O
compatibility	O
updates	O
and	O
other	O
features	O
.	O
</s>
<s>
Hackers	O
and	O
other	O
homebrew	B-Application
enthusiasts	O
then	O
encountered	O
the	O
first	O
trojan	O
for	O
the	O
PSP	B-Operating_System
.	O
</s>
<s>
Users	O
attempting	O
to	O
downgrade	B-Application
their	O
PSP	B-Operating_System
using	O
this	O
software	O
instead	O
found	O
that	O
it	O
was	O
rendered	O
inoperable	O
as	O
this	O
software	O
deleted	O
mandatory/important	O
system	O
files	O
.	O
</s>
<s>
Over	O
the	O
course	O
of	O
2005	O
Sony	O
released	O
six	O
different	O
versions	O
of	O
the	O
firmware	O
and	O
hackers	O
typically	O
responded	O
to	O
it	O
by	O
downgrading	B-Application
to	O
avoid	O
the	O
new	O
security	O
updates	O
.	O
</s>
<s>
In	O
mid-2006	O
,	O
after	O
several	O
months	O
of	O
problems	O
in	O
defeating	O
the	O
PSP	B-Operating_System
's	O
firmware	O
a	O
file	O
was	O
posted	O
online	O
which	O
allowed	O
new	O
PSPs	B-Operating_System
running	O
firmware	O
version	O
2.6	O
to	O
downgrade	B-Application
to	O
1.5	O
so	O
they	O
could	O
then	O
be	O
hacked	O
using	O
older	O
methods	O
.	O
</s>
<s>
Dark	O
AleX	O
(	O
aka	O
Dark_AleX	O
,	O
Dax	O
)	O
was	O
a	O
Serbian	O
programmer	B-General_Concept
who	O
wrote	O
homebrew	B-Application
applications	O
for	O
the	O
PlayStation	B-Operating_System
Portable	I-Operating_System
.	O
</s>
<s>
One	O
of	O
the	O
drawbacks	O
of	O
downgrading	B-Application
the	O
PSP	B-Operating_System
is	O
that	O
new	O
official	O
media	O
may	O
require	O
the	O
presence	O
of	O
a	O
new	O
firmware	O
edition	O
.	O
</s>
<s>
In	O
July	O
2007	O
Dark_AleX	O
officially	O
stopped	O
his	O
work	O
on	O
the	O
PSP	B-Operating_System
,	O
citing	O
perceived	O
problems	O
with	O
Sony	O
as	O
one	O
of	O
the	O
reasons	O
for	O
his	O
departure	O
.	O
</s>
<s>
Custom	O
Firmware	O
allows	O
the	O
running	O
of	O
unsigned	O
code	O
such	O
as	O
homebrew	B-Application
applications	O
and	O
UMD	O
backups	O
,	O
emulators	O
for	O
other	O
consoles	O
,	O
as	O
well	O
as	O
PlayStation	B-Device
games	O
when	O
the	O
disc	O
images	O
are	O
converted	O
into	O
PSP	B-Operating_System
format	O
.	O
</s>
<s>
Half	O
Byte	O
Loader	O
(	O
also	O
known	O
as	O
HBL	O
)	O
is	O
an	O
open	O
source	O
software	O
project	O
that	O
aims	O
at	O
loading	O
homebrew	B-Application
for	O
PlayStation	B-Operating_System
Portable	I-Operating_System
handheld	O
console	O
through	O
user-mode	O
exploits	O
.	O
</s>
<s>
HBL	O
was	O
created	O
initially	O
for	O
the	O
Medal	B-Device
of	I-Device
Honor	I-Device
Heroes	I-Device
exploit	O
.	O
</s>
<s>
An	O
alpha	O
version	O
was	O
released	O
as	O
open	O
source	O
by	O
m0skit0	O
and	O
ab5000	O
in	O
November	O
2009	O
,	O
which	O
ran	O
very	O
simple	O
homebrews	B-Application
.	O
</s>
<s>
When	O
the	O
Patapon	B-Application
2	I-Application
demo	O
exploit	O
was	O
found	O
and	O
leaked	O
,	O
wololo	O
joined	O
the	O
project	O
and	O
proposed	O
to	O
port	O
HBL	O
to	O
this	O
new	O
exploit	O
.	O
</s>
<s>
Other	O
PSP	B-Operating_System
hackers	O
such	O
as	O
Davee	O
and	O
neur0n	O
joined	O
in	O
to	O
help	O
the	O
development	O
of	O
this	O
port	O
.	O
</s>
<s>
HBL	O
for	O
Patapon	B-Application
2	I-Application
passed	O
to	O
beta	O
version	O
,	O
and	O
can	O
be	O
considered	O
the	O
first	O
useful	O
HBL	O
version	O
,	O
released	O
in	O
March	O
2010	O
.	O
</s>
<s>
HBL	O
was	O
also	O
ported	O
to	O
run	O
on	O
Sony	B-Device
PlayStation	I-Device
Vita	O
's	O
PSP	B-Operating_System
emulator	O
with	O
very	O
little	O
modifications	O
.	O
</s>
<s>
Nowadays	O
,	O
the	O
most	O
used	O
and	O
recent	O
PSP	B-Operating_System
CFWs	O
are	O
PRO	O
,	O
ME	O
and	O
ARK	O
.	O
</s>
<s>
An	O
exploit	O
called	O
Infinity	O
allows	O
the	O
user	O
to	O
permanently	O
run	O
a	O
previously	O
installed	O
CFW	O
(	O
like	O
PRO	O
,	O
ME	O
and	O
ARK	O
)	O
on	O
a	O
PSP	B-Operating_System
,	O
i.e.	O
,	O
after	O
restarting	O
the	O
PSP	B-Operating_System
or	O
turning	O
it	O
off	O
and	O
on	O
,	O
the	O
previously	O
installed	O
CFW	O
remains	O
activated	O
without	O
the	O
user	O
having	O
to	O
do	O
any	O
previous	O
step	O
.	O
</s>
<s>
Hackers	O
have	O
stated	O
that	O
the	O
motivation	O
for	O
unlocking	O
the	O
PSP	B-Operating_System
has	O
nothing	O
to	O
do	O
with	O
piracy	O
,	O
but	O
allowing	O
individuals	O
full	O
access	O
to	O
the	O
products	O
they	O
've	O
purchased	O
and	O
the	O
freedom	O
to	O
do	O
what	O
they	O
want	O
with	O
the	O
item	O
as	O
well	O
as	O
the	O
interest	O
in	O
exploring	O
something	O
unknown	O
.	O
</s>
<s>
Fanjita	B-Device
,	O
a	O
member	O
of	O
the	O
hacker	O
group	O
"	O
N00bz	O
!	O
</s>
<s>
They	O
have	O
also	O
stated	O
that	O
the	O
problem	O
is	O
not	O
with	O
homebrew	B-Application
but	O
piracy	O
.	O
</s>
<s>
However	O
their	O
constant	O
firmware	O
updates	O
have	O
been	O
seen	O
as	O
attempts	O
to	O
hamper	O
homebrew	B-Application
development	O
.	O
</s>
<s>
However	O
,	O
Sony	O
has	O
also	O
said	O
that	O
,	O
when	O
questioned	O
about	O
homebrew	B-Application
game	O
support	O
,	O
Jack	O
Tretton	O
,	O
who	O
was	O
Sony	O
Computer	O
Entertainment	O
America	O
's	O
President	O
and	O
CEO	O
at	O
the	O
time	O
replied	O
with	O
,	O
</s>
<s>
We	O
certainly	O
see	O
some	O
of	O
the	O
stuff	O
that	O
has	O
been	O
done	O
via	O
homebrew	B-Application
,	O
and	O
it	O
's	O
incredibly	O
creative	O
.	O
</s>
