<s>
This	O
article	O
covers	O
computer	B-Application
software	I-Application
designed	O
to	O
solve	O
,	O
or	O
assist	O
people	O
in	O
creating	O
or	O
solving	O
,	O
chess	B-Application
problems	O
–	O
puzzles	O
in	O
which	O
pieces	O
are	O
laid	O
out	O
as	O
in	O
a	O
game	O
of	O
chess	B-Application
,	O
and	O
may	O
at	O
times	O
be	O
based	O
upon	O
real	O
games	O
of	O
chess	B-Application
that	O
have	O
been	O
played	O
and	O
recorded	O
,	O
but	O
whose	O
aim	O
is	O
to	O
challenge	O
the	O
problemist	O
to	O
find	O
a	O
solution	O
to	O
the	O
posed	O
situation	O
,	O
within	O
the	O
rules	O
of	O
chess	B-Application
,	O
rather	O
than	O
to	O
play	O
games	O
of	O
chess	B-Application
from	O
the	O
beginning	O
against	O
an	O
opponent	O
.	O
</s>
<s>
This	O
is	O
usually	O
distinct	O
from	O
actually	O
playing	B-Application
and	I-Application
analyzing	I-Application
games	I-Application
of	I-Application
chess	I-Application
.	O
</s>
<s>
Many	O
chess	B-Application
playing	O
programs	O
also	O
have	O
provision	O
for	O
solving	O
some	O
kinds	O
of	O
problem	O
such	O
as	O
checkmate	B-Application
in	O
a	O
certain	O
number	O
of	O
moves	O
(	O
directmates	O
)	O
,	O
and	O
some	O
also	O
have	O
support	O
for	O
helpmates	O
and	O
selfmates	O
.	O
</s>
<s>
Software	O
for	O
chess	B-Application
problems	O
can	O
be	O
used	O
for	O
creating	O
and	O
solving	O
problems	O
,	O
including	O
checking	O
the	O
soundness	O
of	O
a	O
concept	O
and	O
position	O
,	O
storing	O
it	O
in	O
a	O
database	O
,	O
printing	O
and	O
publishing	O
,	O
and	O
saving	O
and	O
exporting	O
the	O
problem	O
.	O
</s>
<s>
As	O
such	O
they	O
can	O
not	O
only	O
solve	O
direct	O
mates	O
,	O
helpmates	O
and	O
selfmates	O
,	O
but	O
at	O
times	O
even	O
problems	O
with	O
fairy	O
pieces	O
and	O
other	O
fairy	O
chess	B-Application
problems	O
.	O
</s>
<s>
First	O
developed	O
in	O
1980	O
by	O
Ilkka	O
Blom	O
,	O
Alybadix	O
is	O
a	O
suite	O
of	O
chess	B-Application
problem	O
solving	O
programs	O
for	O
DOS	B-Device
and	O
Commodore	O
64	O
.	O
</s>
<s>
Popeye	O
is	O
a	O
chess	B-Application
problem-solving	O
software	O
accommodating	O
many	O
fairy	O
chess	B-Application
rules	O
and	O
able	O
to	O
investigate	O
set	O
play	O
and	O
tries	O
.	O
</s>
<s>
Since	O
its	O
origin	O
,	O
Popeye	O
was	O
designed	O
as	O
a	O
general-purpose	O
,	O
extensible	O
tool	O
for	O
checking	O
fairy	O
and	O
heterodox	O
chess	B-Application
problems	O
.	O
</s>
<s>
The	O
original	O
author	O
of	O
Popeye	O
was	O
Philippe	O
Schnoebelen	O
who	O
wrote	O
it	O
in	O
Pascal	B-Application
under	O
MS-DOS	B-Application
around	O
1983-84	O
.	O
</s>
<s>
In	O
1986	O
the	O
code	O
was	O
donated	O
in	O
the	O
spirit	O
of	O
the	O
free	B-Application
software	I-Application
movement	O
.	O
</s>
<s>
Elmar	O
Bartel	O
,	O
Norbert	O
Geissler	O
,	O
Thomas	O
Maeder	O
,	O
Torsten	O
Linss	O
,	O
Stefan	O
Hoening	O
,	O
Stefan	O
Brunzen	O
,	O
Harald	O
Denker	O
,	O
Thomas	O
Bark	O
and	O
Stephen	O
Emmerson	O
,	O
converted	O
Popeye	O
to	O
the	O
C	B-Language
programming	I-Language
language	I-Language
,	O
and	O
now	O
maintain	O
the	O
program	O
.	O
</s>
<s>
Chloe	O
(	O
DOS	B-Device
)	O
and	O
Winchloe	O
(	O
proprietary	O
software	O
)	O
are	O
solving	O
programs	O
written	O
by	O
Christian	O
Poisson	O
.	O
</s>
<s>
Natch	O
and	O
iNatch	O
are	O
freeware	O
programs	O
written	O
by	O
Pascal	B-Application
Wassong	O
for	O
DOS	B-Device
and	O
Linux	O
.	O
</s>
<s>
Natch	O
is	O
a	O
command	O
line	O
utility	O
,	O
but	O
there	O
is	O
a	O
Java	B-Language
based	O
graphical	O
interface	O
.	O
</s>
<s>
iNatch	O
also	O
provides	O
moves	O
with	O
fairy	O
conditions	O
:	O
monochrome	O
chess	B-Application
,	O
Einstein	O
chess	B-Application
,	O
vertical	O
cylinder	O
.	O
</s>
<s>
With	O
Problemist	O
come	O
two	O
TrueType	O
chess	B-Application
fonts	O
,	O
and	O
from	O
its	O
web	O
page	O
one	O
can	O
download	O
more	O
than	O
100,000	O
problems	O
.	O
</s>
<s>
Problemist	O
is	O
the	O
first	O
chess	B-Application
problems	O
exchange	O
format	O
.	O
</s>
<s>
Jacobi	O
is	O
a	O
program	O
to	O
solve	O
fairy	O
chess	B-Application
proof	O
game	O
problems	O
by	O
François	O
Labelle	O
.	O
</s>
<s>
In	O
2003	O
,	O
Labelle	O
already	O
developed	O
chess-related	O
programs	O
and	O
published	O
computer-generated	O
chess	B-Application
problems	O
.	O
</s>
<s>
allowing	O
Chest	O
to	O
be	O
used	O
as	O
solving	O
engine	O
in	O
any	O
UCI-capable	O
chess	B-Application
GUI	O
.	O
</s>
<s>
Chess	B-Application
Problem	O
Database	O
Server	O
is	O
online	O
database	O
of	O
all	O
types	O
of	O
chess	B-Application
problems	O
,	O
maintained	O
by	O
Gerd	O
Wilts	O
,	O
hosted	O
by	O
Die	O
Schwalbe	O
.	O
</s>
<s>
Diagram	O
is	O
a	O
style	O
file	O
for	O
LaTeX	B-Application
for	O
typesetting	O
chess	B-Application
diagrams	O
.	O
</s>
<s>
The	O
style	O
was	O
originally	O
created	O
by	O
Thomas	O
Brand	O
and	O
further	O
developed	O
by	O
Stefan	O
Hoening	O
,	O
both	O
based	O
on	O
ideas	O
of	O
a	O
TeX	B-Application
package	O
from	O
Elmar	O
Bartel	O
.	O
</s>
<s>
The	O
style	O
is	O
used	O
to	O
produce	O
the	O
German	O
problem	O
chess	B-Application
magazine	O
Die	O
Schwalbe	O
.	O
</s>
