<s>
GraphML	B-Language
is	O
an	O
XML-based	O
file	O
format	O
for	O
graphs	O
.	O
</s>
<s>
The	O
GraphML	B-Language
file	O
format	O
results	O
from	O
the	O
joint	O
effort	O
of	O
the	O
graph	O
drawing	O
community	O
to	O
define	O
a	O
common	O
format	O
for	O
exchanging	O
graph	O
structure	O
data	O
.	O
</s>
<s>
It	O
uses	O
an	O
XML-based	O
syntax	O
and	O
supports	O
the	O
entire	O
range	O
of	O
possible	O
graph	O
structure	O
constellations	O
including	O
directed	O
,	O
undirected	O
,	O
mixed	O
graphs	O
,	O
hypergraphs	O
,	O
and	O
application-specific	O
attributes	O
.	O
</s>
<s>
A	O
GraphML	B-Language
file	O
consists	O
of	O
an	O
XML	B-Protocol
file	O
containing	O
a	O
graph	O
element	O
,	O
within	O
which	O
is	O
an	O
unordered	O
sequence	O
of	O
node	O
and	O
edge	O
elements	O
.	O
</s>
<s>
Additional	O
features	O
of	O
the	O
GraphML	B-Language
language	O
allow	O
its	O
users	O
to	O
specify	O
whether	O
edges	O
are	O
directed	O
or	O
undirected	O
,	O
and	O
to	O
associate	O
additional	O
data	O
with	O
vertices	O
or	O
edges	O
.	O
</s>
