<s>
DeHackEd	B-Application
is	O
an	O
editor	O
created	O
by	O
Greg	O
Lewis	O
for	O
the	O
executable	B-Application
of	O
the	O
original	O
Doom	B-Application
that	O
allows	O
the	O
operation	O
of	O
the	O
executable	B-Application
to	O
be	O
changed	O
.	O
</s>
<s>
Modifications	O
can	O
be	O
distributed	O
in	O
the	O
form	O
of	O
DeHackEd	B-Application
"	O
patches	O
"	O
which	O
can	O
be	O
applied	O
to	O
the	O
executable	B-Application
.	O
</s>
<s>
At	O
the	O
time	O
DeHackEd	B-Application
was	O
released	O
,	O
Doom	B-Application
was	O
a	O
closed-source	O
program	O
,	O
and	O
thus	O
to	O
allow	O
new	O
features	O
to	O
be	O
made	O
available	O
,	O
the	O
only	O
choice	O
was	O
to	O
patch	O
the	O
executable	B-Application
(	O
as	O
opposed	O
to	O
being	O
able	O
to	O
change	O
the	O
source	O
,	O
which	O
can	O
now	O
be	O
done	O
since	O
id	O
Software	O
has	O
made	O
public	O
a	O
release	O
of	O
the	O
sources	O
)	O
.	O
</s>
<s>
Even	O
though	O
many	O
advanced	O
effects	O
can	O
be	O
achieved	O
with	O
DeHackEd	B-Application
,	O
it	O
does	O
not	O
offer	O
the	O
complete	O
flexibility	O
that	O
a	O
custom	O
source	O
port	O
can	O
provide	O
.	O
</s>
<s>
Older	O
DeHackEd	B-Application
patches	O
use	O
a	O
binary	O
format	O
of	O
data	O
to	O
be	O
applied	O
to	O
an	O
executable	B-Application
file	I-Application
using	O
the	O
DeHackEd	B-Application
patching	O
utility	O
.	O
</s>
<s>
Later	O
versions	O
of	O
DeHackEd	B-Application
save	O
their	O
patches	O
in	O
a	O
human-readable	B-General_Concept
plain	O
text	O
format	O
that	O
can	O
be	O
edited	O
with	O
any	O
text	O
editor	O
.	O
</s>
<s>
Boom	O
included	O
the	O
ability	O
to	O
load	O
DeHackEd	B-Application
patches	O
and	O
effect	O
changes	O
to	O
the	O
game	O
upon	O
startup	O
without	O
any	O
modification	O
to	O
the	O
executable	B-Application
file	I-Application
.	O
</s>
<s>
Other	O
source	O
ports	O
added	O
similar	O
functionality	O
,	O
and	O
command-line	O
loadable	O
DeHackEd	B-Application
support	O
is	O
now	O
common	O
with	O
most	O
modern	O
source	O
ports	O
.	O
</s>
<s>
Boom	O
also	O
provided	O
the	O
BEX	O
(	O
Boom	O
EXtended	O
)	O
extensions	O
for	O
DeHackEd	B-Application
support	O
.	O
</s>
