<s>
The	O
Browser	B-General_Concept
Object	I-General_Concept
Model	I-General_Concept
(	O
BOM	O
)	O
is	O
a	O
browser-specific	O
convention	O
referring	O
to	O
all	O
the	O
objects	O
exposed	O
by	O
the	O
web	B-Application
browser	I-Application
.	O
</s>
<s>
Unlike	O
the	O
Document	B-General_Concept
Object	I-General_Concept
Model	I-General_Concept
,	O
there	O
is	O
no	O
standard	O
for	O
implementation	O
and	O
no	O
strict	O
definition	O
,	O
so	O
browser	B-Application
vendors	O
are	O
free	O
to	O
implement	O
the	O
BOM	O
in	O
any	O
way	O
they	O
wish	O
.	O
</s>
<s>
That	O
which	O
we	O
see	O
as	O
a	O
window	O
displaying	O
a	O
document	O
,	O
the	O
browser	B-Application
program	O
sees	O
as	O
a	O
hierarchical	O
collection	B-Library
of	O
objects	O
.	O
</s>
<s>
When	O
the	O
browser	B-Application
parses	O
a	O
document	O
,	O
it	O
creates	O
a	O
collection	B-Library
of	O
objects	O
that	O
define	O
the	O
document	O
and	O
detail	O
how	O
it	O
should	O
be	O
displayed	O
.	O
</s>
<s>
The	O
object	O
the	O
browser	B-Application
creates	O
is	O
known	O
as	O
the	O
Document	B-General_Concept
Object	I-General_Concept
Model	I-General_Concept
(	O
DOM	B-General_Concept
)	O
.	O
</s>
<s>
It	O
is	O
part	O
of	O
a	O
larger	O
collection	B-Library
of	O
objects	O
that	O
the	O
browser	B-Application
makes	O
use	O
of	O
.	O
</s>
<s>
This	O
collection	B-Library
of	O
browser	B-Application
objects	O
is	O
collectively	O
known	O
as	O
the	O
Browser	B-General_Concept
Object	I-General_Concept
Model	I-General_Concept
,	O
or	O
BOM	O
.	O
</s>
