<s>
Sjeng	B-Application
is	O
a	O
chess	B-Application
engine	I-Application
written	O
by	O
Gian-Carlo	O
Pascutto	O
based	O
on	O
Faile	O
,	O
written	O
by	O
Adrien	O
Regimbald	O
.	O
</s>
<s>
There	O
are	O
two	O
major	O
versions	O
of	O
Sjeng	B-Application
:	O
the	O
original	O
open	B-Application
source	I-Application
version	O
called	O
Sjeng	B-Application
(	O
also	O
now	O
known	O
as	O
Sjeng	B-Application
old	O
or	O
Sjeng	B-Application
free	O
)	O
and	O
Deep	B-Application
Sjeng	I-Application
,	O
a	O
closed	O
source	O
commercial	O
version	O
.	O
</s>
<s>
Unlike	O
most	O
other	O
chess	B-Application
engines	I-Application
Sjeng	B-Application
supports	O
several	O
popular	O
chess	O
variants	O
:	O
Crazyhouse	O
,	O
Suicide	O
,	O
Losers	O
and	O
,	O
when	O
playing	O
on	O
a	O
chess	O
server	O
,	O
Bughouse	O
.	O
</s>
<s>
Starting	O
with	O
Mac	B-Application
OSX	I-Application
10.4	I-Application
Sjeng	B-Application
has	O
been	O
distributed	O
as	O
the	O
engine	O
behind	O
the	O
graphical	O
“	O
Chess	O
”	O
Mac	O
application	O
.	O
</s>
<s>
The	O
first	O
version	O
with	O
source	O
code	O
under	O
the	O
GPL	B-License
was	O
Sjeng	B-Application
7	O
released	O
to	O
SourceForge	B-Application
on	O
4/15/2000	O
.	O
</s>
<s>
The	O
last	O
open	B-Application
source	I-Application
version	O
was	O
Sjeng	B-Application
11.2	O
,	O
released	O
on	O
1/2/2002	O
.	O
</s>
<s>
With	O
version	O
12	O
Sjeng	B-Application
went	O
back	O
to	O
being	O
closed	O
source	O
,	O
although	O
still	O
free	O
.	O
</s>
<s>
Version	O
12	O
contained	O
many	O
changes	O
,	O
including	O
a	O
switch	O
to	O
bitboard	B-Application
architecture	O
and	O
the	O
removal	O
of	O
variant	O
support	O
.	O
</s>
<s>
The	O
next	O
iteration	O
of	O
the	O
chess	B-Application
engine	I-Application
was	O
named	O
Deep	B-Application
Sjeng	I-Application
1.0	O
and	O
released	O
as	O
a	O
commercial	O
program	O
on	O
3/3/2003	O
.	O
</s>
<s>
It	O
featured	O
multiprocessor	B-Operating_System
support	O
and	O
was	O
estimated	O
to	O
be	O
200	O
rating	O
points	O
stronger	O
than	O
Sjeng	B-Application
Free	O
.	O
</s>
<s>
The	O
last	O
version	O
of	O
Deep	B-Application
Sjeng	I-Application
won	O
the	O
World	O
Computer	O
Speed	O
Chess	O
Championship	O
in	O
2008	O
.	O
</s>
<s>
Deep	B-Application
Sjeng	I-Application
is	O
no	O
longer	O
for	O
sale	O
.	O
</s>
<s>
Deep	B-Application
Sjeng	I-Application
participated	O
in	O
six	O
World	O
Computer	O
Chess	O
Championships	O
,	O
then	O
retired	O
after	O
tying	O
for	O
first	O
place	O
in	O
the	O
17th	O
Championship	O
.	O
</s>
<s>
Deep	B-Application
Sjeng	I-Application
actually	O
tied	O
for	O
second	O
place	O
,	O
however	O
the	O
winner	O
,	O
Rybka	B-Application
,	O
was	O
disqualified	O
for	O
plagiarism	O
.	O
</s>
<s>
Sjeng	B-Application
won	O
the	O
World	O
Computer	O
Speed	O
Chess	O
Championship	O
in	O
2008	O
,	O
and	O
the	O
World	O
Computer	O
Chess	O
Championship	O
in	O
2009	O
.	O
</s>
