<s>
Game	B-Language
Description	I-Language
Language	I-Language
,	O
or	O
GDL	O
,	O
is	O
a	O
logic	B-Language
programming	I-Language
language	I-Language
designed	O
by	O
Michael	O
Genesereth	O
for	O
general	B-Algorithm
game	I-Algorithm
playing	I-Algorithm
,	O
as	O
part	O
of	O
the	O
General	B-Algorithm
Game	I-Algorithm
Playing	I-Algorithm
Project	O
at	O
Stanford	O
University	O
.	O
</s>
<s>
Quoted	O
in	O
an	O
article	O
in	O
New	O
Scientist	O
,	O
Genesereth	O
pointed	O
out	O
that	O
although	O
Deep	B-General_Concept
Blue	I-General_Concept
is	O
able	O
to	O
play	O
chess	O
at	O
a	O
grandmaster	O
level	O
,	O
it	O
is	O
incapable	O
of	O
playing	O
checkers	O
at	O
all	O
because	O
it	O
is	O
a	O
specialized	O
game	O
player	O
.	O
</s>
<s>
GDL	O
is	O
a	O
variant	O
of	O
Datalog	B-Language
,	O
and	O
the	O
syntax	B-Application
is	O
largely	O
the	O
same	O
.	O
</s>
<s>
GDL-II	O
,	O
the	O
Game	B-Language
Description	I-Language
Language	I-Language
for	O
Incomplete	O
Information	O
Games	O
,	O
extends	O
GDL	O
by	O
two	O
keywords	O
that	O
allow	O
for	O
the	O
description	O
of	O
elements	O
of	O
chance	O
and	O
incomplete	O
information	O
:	O
</s>
<s>
The	O
following	O
is	O
an	O
example	O
from	O
a	O
GDL-II	O
description	O
of	O
the	O
card	O
game	O
Texas	B-Device
hold	I-Device
'	I-Device
em	I-Device
:	O
</s>
<s>
Michael	O
Thielscher	O
also	O
created	O
a	O
further	O
extension	O
,	O
GDL-III	O
,	O
a	O
general	O
game	B-Language
description	I-Language
language	I-Language
with	O
imperfect	O
information	O
and	O
introspection	O
,	O
that	O
supports	O
the	O
specification	O
of	O
epistemic	O
games	O
—	O
ones	O
characterised	O
by	O
rules	O
that	O
depend	O
on	O
the	O
knowledge	O
of	O
players	O
.	O
</s>
