<s>
Shane	B-Language
's	I-Language
Chess	I-Language
Information	I-Language
Database	I-Language
(	O
Scid	B-Language
)	O
is	O
a	O
free	B-Application
and	O
open	B-Application
source	I-Application
UNIX	B-Application
,	O
Windows	B-Application
,	O
Linux	B-Application
,	O
and	O
Mac	B-Application
application	O
for	O
viewing	O
and	O
maintaining	O
large	O
databases	O
of	O
chess	B-Application
games	O
.	O
</s>
<s>
It	O
has	O
features	O
comparable	O
to	O
popular	O
commercial	O
chess	B-Application
software	I-Application
.	O
</s>
<s>
Scid	B-Language
is	O
written	O
in	O
Tcl/Tk	B-Application
and	O
C++	O
.	O
</s>
<s>
Scid	B-Language
has	O
undergone	O
several	O
stages	O
of	O
development	O
,	O
firstly	O
by	O
Shane	O
Hudson	O
,	O
then	O
by	O
Pascal	O
Georges	O
.	O
</s>
<s>
Scid	B-Language
is	O
a	O
powerful	O
Chess	B-Application
Toolkit	O
with	O
many	O
features	O
.	O
</s>
<s>
It	O
can	O
interface	O
with	O
XBoard	B-Application
engines	O
(	O
such	O
as	O
Crafty	B-Application
and	O
GNU	B-Application
Chess	I-Application
)	O
,	O
and	O
UCI	B-General_Concept
engines	O
(	O
e.g.	O
</s>
<s>
Fruit	B-Application
,	O
Rybka	B-Application
and	O
Stockfish	B-Application
)	O
.	O
</s>
<s>
Using	O
Scid	B-Language
,	O
one	O
may	O
play	O
games	O
against	O
human	O
opponents	O
(	O
on	O
the	O
Free	B-Application
Internet	O
Chess	B-Application
Server	O
)	O
,	O
or	O
computer	O
opponents	O
.	O
</s>
<s>
Scid	B-Language
's	O
speed	O
is	O
due	O
to	O
its	O
storing	O
chess	B-Application
games	O
in	O
its	O
own	O
compact	O
database	O
format	O
(	O
si4	O
)	O
,	O
but	O
it	O
also	O
supports	O
the	O
popular	O
portable	O
game	O
notation	O
(	O
PGN	O
)	O
.	O
</s>
<s>
There	O
are	O
multiple	O
projects	O
related	O
to	O
Scid	B-Language
,	O
all	O
using	O
the	O
si4	O
database	O
format	O
.	O
</s>
<s>
ChessDB	O
was	O
the	O
first	O
Scid	B-Language
fork	O
.	O
</s>
<s>
Scid	B-Language
vs.	O
PC	O
has	O
been	O
in	O
development	O
since	O
2009	O
,	O
and	O
has	O
an	O
improved	O
interface	O
.	O
</s>
<s>
ChessX	O
replaces	O
Tcl/Tk	B-Application
with	O
Qt	B-Language
.	O
</s>
<s>
Scidb	O
(	O
written	O
in	O
Tcl/C	O
++	O
)	O
,	O
implements	O
many	O
chess	B-Application
variants	O
and	O
many	O
read/write	O
formats	O
.	O
</s>
<s>
Scid	B-Language
on	O
the	O
go	O
is	O
a	O
browser	O
for	O
Scid	B-Language
database	O
files	O
for	O
Android	B-Application
.	O
</s>
