<s>
Many	O
of	O
the	O
most	O
important	O
games	O
are	O
now	O
available	O
in	O
machine-readable	O
form	O
,	O
using	O
one	O
of	O
a	O
small	O
number	O
of	O
digital	O
Go	B-Application
file	I-Application
formats	I-Application
.	O
</s>
<s>
Go	B-Application
file	I-Application
formats	I-Application
are	O
used	O
to	O
record	O
the	O
moves	O
in	O
a	O
game	O
of	O
Go	O
or	O
for	O
demonstrations	O
,	O
game	O
reviews	O
,	O
and	O
tsumego	O
(	O
Go	O
problems	O
)	O
.	O
</s>
