<s>
Software	B-Application
cracking	I-Application
(	O
known	O
as	O
"	O
breaking	O
"	O
mostly	O
in	O
the	O
1980s	O
)	O
is	O
an	O
act	O
of	O
removing	O
copy	B-Application
protection	I-Application
from	O
a	O
software	O
.	O
</s>
<s>
Copy	B-Application
protection	I-Application
can	O
be	O
removed	O
by	O
applying	O
a	O
specific	O
crack	O
.	O
</s>
<s>
Software	B-Application
cracking	I-Application
contributes	O
to	O
the	O
rise	O
of	O
online	O
piracy	O
where	O
pirated	O
software	O
is	O
distributed	O
to	O
end-users	O
through	O
filesharing	O
sites	O
like	O
BitTorrent	B-Protocol
,	O
One	O
click	O
hosting	O
(	O
OCH	O
)	O
,	O
or	O
via	O
Usenet	B-Application
downloads	O
,	O
or	O
by	O
downloading	O
bundles	O
of	O
the	O
original	O
software	O
with	O
cracks	O
or	O
keygens	O
.	O
</s>
<s>
Some	O
of	O
these	O
tools	O
are	O
called	O
keygen	O
,	O
patch	O
,	O
loader	B-Operating_System
,	O
or	O
no-disc	O
crack	O
.	O
</s>
<s>
A	O
patch	O
is	O
a	O
small	O
computer	O
program	O
that	O
modifies	O
the	O
machine	B-Language
code	I-Language
of	O
another	O
program	O
.	O
</s>
<s>
This	O
has	O
the	O
advantage	O
for	O
a	O
cracker	B-Application
to	O
not	O
include	O
a	O
large	O
executable	O
in	O
a	O
release	O
when	O
only	O
a	O
few	O
bytes	O
are	O
changed	O
.	O
</s>
<s>
A	O
loader	B-Operating_System
modifies	O
the	O
startup	O
flow	O
of	O
a	O
program	O
and	O
does	O
not	O
remove	O
the	O
protection	O
but	O
circumvents	O
it	O
.	O
</s>
<s>
A	O
well-known	O
example	O
of	O
a	O
loader	B-Operating_System
is	O
a	O
trainer	O
used	O
to	O
cheat	O
in	O
games	O
.	O
</s>
<s>
Fairlight	O
pointed	O
out	O
in	O
one	O
of	O
their	O
.nfo	B-Protocol
files	O
that	O
these	O
type	O
of	O
cracks	O
are	O
not	O
allowed	O
for	O
warez	B-Application
scene	I-Application
game	O
releases	O
.	O
</s>
<s>
Software	B-Application
cracking	I-Application
is	O
closely	O
related	O
to	O
reverse	O
engineering	O
because	O
the	O
process	O
of	O
attacking	O
a	O
copy	B-Application
protection	I-Application
technology	O
,	O
is	O
similar	O
to	O
the	O
process	O
of	O
reverse	O
engineering	O
.	O
</s>
<s>
It	O
might	O
be	O
legal	O
to	O
use	O
cracked	B-Application
software	I-Application
in	O
certain	O
circumstances	O
.	O
</s>
<s>
Educational	O
resources	O
for	O
reverse	O
engineering	O
and	O
software	B-Application
cracking	I-Application
are	O
,	O
however	O
,	O
legal	O
and	O
available	O
in	O
the	O
form	O
of	O
Crackme	O
programs	O
.	O
</s>
<s>
Therefore	O
,	O
software	O
producers	O
generally	O
tried	O
to	O
implement	O
some	O
form	O
of	O
copy	B-Application
protection	I-Application
before	O
releasing	O
it	O
to	O
the	O
market	O
.	O
</s>
<s>
In	O
1984	O
,	O
Laind	O
Huntsman	O
,	O
the	O
head	O
of	O
software	O
development	O
for	O
Formaster	O
,	O
a	O
software	B-Application
protection	I-Application
company	O
,	O
commented	O
that	O
"	O
no	O
protection	O
system	O
has	O
remained	O
uncracked	O
by	O
enterprising	O
programmers	O
for	O
more	O
than	O
a	O
few	O
months	O
"	O
.	O
</s>
<s>
In	O
2001	O
,	O
Dan	O
S	O
.	O
Wallach	O
,	O
a	O
professor	O
from	O
Rice	O
University	O
,	O
argued	O
that	O
"	O
those	O
determined	O
to	O
bypass	O
copy-protection	B-Application
have	O
always	O
found	O
ways	O
to	O
do	O
so	O
–	O
and	O
always	O
will	O
"	O
.	O
</s>
<s>
Most	O
of	O
the	O
early	O
software	B-Application
crackers	I-Application
were	O
computer	O
hobbyists	O
who	O
often	O
formed	O
groups	O
that	O
competed	O
against	O
each	O
other	O
in	O
the	O
cracking	O
and	O
spreading	O
of	O
software	O
.	O
</s>
<s>
Breaking	O
a	O
new	O
copy	B-Application
protection	I-Application
scheme	O
as	O
quickly	O
as	O
possible	O
was	O
often	O
regarded	O
as	O
an	O
opportunity	O
to	O
demonstrate	O
one	O
's	O
technical	O
superiority	O
rather	O
than	O
a	O
possibility	O
of	O
money-making	O
.	O
</s>
<s>
Software	B-Application
crackers	I-Application
usually	O
did	O
not	O
benefit	O
materially	O
from	O
their	O
actions	O
and	O
their	O
motivation	O
was	O
the	O
challenge	O
itself	O
of	O
removing	O
the	O
protection	O
.	O
</s>
<s>
Some	O
low	O
skilled	O
hobbyists	O
would	O
take	O
already	O
cracked	B-Application
software	I-Application
and	O
edit	O
various	O
unencrypted	O
strings	O
of	O
text	O
in	O
it	O
to	O
change	O
messages	O
a	O
game	O
would	O
tell	O
a	O
game	O
player	O
,	O
often	O
something	O
considered	O
vulgar	O
.	O
</s>
<s>
The	O
cracker	B-Application
groups	O
of	O
the	O
1980s	O
started	O
to	O
advertise	O
themselves	O
and	O
their	O
skills	O
by	O
attaching	O
animated	O
screens	O
known	O
as	O
crack	O
intros	O
in	O
the	O
software	O
programs	O
they	O
cracked	O
and	O
released	O
.	O
</s>
<s>
Demoscene	O
started	O
to	O
separate	O
itself	O
from	O
the	O
illegal	O
"	O
warez	B-Application
scene	I-Application
"	O
during	O
the	O
1990s	O
and	O
is	O
now	O
regarded	O
as	O
a	O
completely	O
different	O
subculture	O
.	O
</s>
<s>
Many	O
software	B-Application
crackers	I-Application
have	O
later	O
grown	O
into	O
extremely	O
capable	O
software	O
reverse	O
engineers	O
;	O
the	O
deep	O
knowledge	O
of	O
assembly	O
required	O
in	O
order	O
to	O
crack	O
protections	O
enables	O
them	O
to	O
reverse	O
engineer	O
drivers	B-Application
in	O
order	O
to	O
port	O
them	O
from	O
binary-only	O
drivers	B-Application
for	O
Windows	B-Application
to	O
drivers	B-Application
with	O
source	O
code	O
for	O
Linux	B-Application
and	O
other	O
free	B-Application
operating	O
systems	O
.	O
</s>
<s>
With	O
the	O
rise	O
of	O
the	O
Internet	O
,	O
software	B-Application
crackers	I-Application
developed	O
secretive	O
online	O
organizations	O
.	O
</s>
<s>
In	O
the	O
latter	O
half	O
of	O
the	O
nineties	O
,	O
one	O
of	O
the	O
most	O
respected	O
sources	O
of	O
information	O
about	O
"	O
software	B-Application
protection	I-Application
reversing	O
"	O
was	O
Fravia	O
's	O
website	O
.	O
</s>
<s>
In	O
2017	O
,	O
a	O
group	O
of	O
software	B-Application
crackers	I-Application
started	O
a	O
project	O
to	O
preserve	O
Apple	B-Device
II	I-Device
softwares	O
by	O
removing	O
the	O
inherent	O
Apple	B-Device
II	I-Device
copy	B-Application
protection	I-Application
.	O
</s>
<s>
The	O
High	O
Cracking	O
University	O
( +HCU	O
)	O
was	O
founded	O
by	O
Old	O
Red	O
Cracker	B-Application
( +ORC	O
)	O
,	O
considered	O
a	O
genius	O
of	O
reverse	O
engineering	O
and	O
a	O
legendary	O
figure	O
in	O
RCE	O
,	O
to	O
advance	O
research	O
into	O
Reverse	O
Code	O
Engineering	O
(	O
RCE	O
)	O
.	O
</s>
<s>
Amongst	O
the	O
students	O
of	O
+HCU	O
were	O
the	O
top	O
of	O
the	O
elite	O
Windows	B-Application
reversers	O
worldwide	O
.	O
</s>
<s>
Nowadays	O
most	O
of	O
the	O
graduates	O
of	O
+HCU	O
have	O
migrated	O
to	O
Linux	B-Application
and	O
few	O
have	O
remained	O
as	O
Windows	B-Application
reversers	O
.	O
</s>
<s>
The	O
most	O
common	O
software	B-Application
crack	I-Application
is	O
the	O
modification	O
of	O
an	O
application	O
's	O
binary	O
to	O
cause	O
or	O
prevent	O
a	O
specific	O
key	O
branch	O
in	O
the	O
program	O
's	O
execution	O
.	O
</s>
<s>
This	O
is	O
accomplished	O
by	O
reverse	O
engineering	O
the	O
compiled	O
program	O
code	O
using	O
a	O
debugger	B-Application
such	O
as	O
SoftICE	B-Application
,	O
OllyDbg	B-Application
,	O
GDB	B-Language
,	O
or	O
MacsBug	B-Operating_System
until	O
the	O
software	B-Application
cracker	I-Application
reaches	O
the	O
subroutine	O
that	O
contains	O
the	O
primary	O
method	O
of	O
protecting	O
the	O
software	O
(	O
or	O
by	O
disassembling	O
an	O
executable	O
file	O
with	O
a	O
program	O
such	O
as	O
IDA	B-Application
)	O
.	O
</s>
<s>
The	O
binary	O
is	O
then	O
modified	O
using	O
the	O
debugger	B-Application
or	O
a	O
hex	B-Application
editor	I-Application
such	O
as	O
HIEW	B-Application
or	O
monitor	B-General_Concept
in	O
a	O
manner	O
that	O
replaces	O
a	O
prior	O
branching	O
opcode	B-Language
with	O
its	O
complement	O
or	O
a	O
NOP	B-Language
opcode	B-Language
so	O
the	O
key	O
branch	O
will	O
either	O
always	O
execute	O
a	O
specific	O
subroutine	O
or	O
skip	O
over	O
it	O
.	O
</s>
<s>
Almost	O
all	O
common	O
software	B-Application
cracks	I-Application
are	O
a	O
variation	O
of	O
this	O
type	O
.	O
</s>
<s>
Proprietary	B-Application
software	I-Application
developers	O
are	O
constantly	O
developing	O
techniques	O
such	O
as	O
code	O
obfuscation	O
,	O
encryption	O
,	O
and	O
self-modifying	B-Application
code	I-Application
to	O
make	O
this	O
modification	O
increasingly	O
difficult	O
.	O
</s>
<s>
Even	O
with	O
these	O
measures	O
being	O
taken	O
,	O
developers	O
struggle	O
to	O
combat	O
software	B-Application
cracking	I-Application
.	O
</s>
<s>
These	O
cracks	O
are	O
usually	O
programs	O
that	O
alter	O
the	O
program	O
executable	O
and	O
sometimes	O
the	O
.dll	B-Library
or	I-Library
.so	I-Library
linked	O
to	O
the	O
application	O
and	O
the	O
process	O
of	O
altering	O
the	O
original	O
binary	O
files	O
is	O
called	O
patching	O
.	O
</s>
<s>
Similar	O
cracks	O
are	O
available	O
for	O
software	O
that	O
requires	O
a	O
hardware	O
dongle	B-Device
.	O
</s>
<s>
A	O
company	O
can	O
also	O
break	O
the	O
copy	B-Application
protection	I-Application
of	O
programs	O
that	O
they	O
have	O
legally	O
purchased	O
but	O
that	O
are	O
licensed	B-License
to	O
particular	O
hardware	O
,	O
so	O
that	O
there	O
is	O
no	O
risk	O
of	O
downtime	O
due	O
to	O
hardware	O
failure	O
(	O
and	O
,	O
of	O
course	O
,	O
no	O
need	O
to	O
restrict	O
oneself	O
to	O
running	O
the	O
software	O
on	O
bought	O
hardware	O
only	O
)	O
.	O
</s>
<s>
Another	O
method	O
is	O
the	O
use	O
of	O
special	O
software	O
such	O
as	O
CloneCD	B-Application
to	O
scan	O
for	O
the	O
use	O
of	O
a	O
commercial	O
copy	B-Application
protection	I-Application
application	O
.	O
</s>
<s>
After	O
discovering	O
the	O
software	O
used	O
to	O
protect	O
the	O
application	O
,	O
another	O
tool	O
may	O
be	O
used	O
to	O
remove	O
the	O
copy	B-Application
protection	I-Application
from	O
the	O
software	O
on	O
the	O
CD	B-Device
or	O
DVD	O
.	O
</s>
<s>
This	O
may	O
enable	O
another	O
program	O
such	O
as	O
Alcohol	B-Application
120%	I-Application
,	O
CloneDVD	B-Application
,	O
Game	B-Application
Jackal	I-Application
,	O
or	O
Daemon	B-Application
Tools	I-Application
to	O
copy	O
the	O
protected	O
software	O
to	O
a	O
user	O
's	O
hard	O
disk	O
.	O
</s>
<s>
Popular	O
commercial	O
copy	B-Application
protection	I-Application
applications	O
which	O
may	O
be	O
scanned	O
for	O
include	O
SafeDisc	O
and	O
StarForce	O
.	O
</s>
<s>
In	O
other	O
cases	O
,	O
it	O
might	O
be	O
possible	O
to	O
decompile	B-Application
a	O
program	O
in	O
order	O
to	O
get	O
access	O
to	O
the	O
original	O
source	O
code	O
or	O
code	O
on	O
a	O
level	B-Language
higher	I-Language
than	O
machine	B-Language
code	I-Language
.	O
</s>
<s>
This	O
is	O
often	O
possible	O
with	O
scripting	B-Language
languages	I-Language
and	O
languages	O
utilizing	O
JIT	O
compilation	O
.	O
</s>
<s>
Java	B-Language
's	I-Language
bytecode	O
also	O
works	O
in	O
a	O
similar	O
fashion	O
in	O
which	O
there	O
is	O
an	O
intermediate	O
language	O
before	O
the	O
program	O
is	O
compiled	O
to	O
run	O
on	O
the	O
platform	O
dependent	O
machine	B-Language
code	I-Language
.	O
</s>
<s>
Advanced	O
reverse	O
engineering	O
for	O
protections	O
such	O
as	O
SecuROM	B-Operating_System
,	O
SafeDisc	O
,	O
StarForce	O
,	O
or	O
Denuvo	B-Application
requires	O
a	O
cracker	B-Application
,	O
or	O
many	O
crackers	B-Application
to	O
spend	O
much	O
more	O
time	O
studying	O
the	O
protection	O
,	O
eventually	O
finding	O
every	O
flaw	O
within	O
the	O
protection	O
code	O
,	O
and	O
then	O
coding	O
their	O
own	O
tools	O
to	O
"	O
unwrap	O
"	O
the	O
protection	O
automatically	O
from	O
executable	O
(	O
.EXE	O
)	O
and	O
library	O
(	O
.DLL	O
)	O
files	O
.	O
</s>
<s>
There	O
are	O
a	O
number	O
of	O
sites	O
on	O
the	O
Internet	O
that	O
let	O
users	O
download	O
cracks	O
produced	O
by	O
warez	B-Application
groups	I-Application
for	O
popular	O
games	O
and	O
applications	O
(	O
although	O
at	O
the	O
danger	O
of	O
acquiring	O
malicious	O
software	O
that	O
is	O
sometimes	O
distributed	O
via	O
such	O
sites	O
)	O
.	O
</s>
<s>
Software	B-Application
cracking	I-Application
led	O
to	O
the	O
distribution	O
of	O
pirated	O
software	O
around	O
the	O
world	O
(	O
software	O
piracy	O
)	O
.	O
</s>
