<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
particularly	O
in	O
human-computer	O
interaction	O
,	O
presentation	B-General_Concept
semantics	I-General_Concept
specify	O
how	O
a	O
particular	O
piece	O
of	O
a	O
formal	O
language	O
is	O
represented	O
in	O
a	O
distinguished	O
manner	O
accessible	O
to	O
human	O
senses	O
,	O
usually	O
human	O
vision	O
.	O
</s>
<s>
For	O
example	O
,	O
saying	O
that	O
<bold> ... </bold>	O
must	O
render	O
the	O
text	O
between	O
these	O
constructs	O
using	O
some	O
bold	O
typeface	O
is	O
a	O
specification	O
of	O
presentation	B-General_Concept
semantics	I-General_Concept
for	O
that	O
syntax	B-Application
.	O
</s>
<s>
Many	O
markup	O
languages	O
,	O
including	O
HTML	B-Language
,	O
DSSSL	B-Language
,	O
and	O
XSL-FO	B-Language
,	O
have	O
presentation	B-General_Concept
semantics	I-General_Concept
,	O
but	O
others	O
,	O
such	O
as	O
XML	B-Protocol
,	O
do	O
not	O
.	O
</s>
<s>
Character	B-General_Concept
encoding	I-General_Concept
standards	O
,	O
such	O
as	O
Unicode	O
,	O
also	O
have	O
presentation	B-General_Concept
semantics	I-General_Concept
.	O
</s>
<s>
One	O
of	O
the	O
main	O
goals	O
of	O
style	B-Language
sheet	I-Language
languages	I-Language
is	O
to	O
separate	O
the	O
syntax	B-Application
that	O
defines	O
document	O
content	O
from	O
the	O
syntax	B-Application
endowed	O
with	O
presentation	B-General_Concept
semantics	I-General_Concept
.	O
</s>
<s>
This	O
is	O
the	O
norm	O
on	O
the	O
World	O
Wide	O
Web	O
,	O
where	O
the	O
Cascading	B-Language
Style	I-Language
Sheets	I-Language
language	O
provides	O
a	O
large	O
collection	O
of	O
presentation	B-General_Concept
semantics	I-General_Concept
for	O
HTML	B-Language
documents	O
.	O
</s>
