<s>
OPOS	B-Library
,	O
full	O
name	O
OLE	B-Operating_System
for	O
Retail	O
POS	O
,	O
a	O
platform	O
specific	O
implementation	O
of	O
UnifiedPOS	B-Application
,	O
is	O
a	O
point	O
of	O
sale	O
device	O
standard	O
for	O
Microsoft	O
Windows	O
operating	B-General_Concept
systems	I-General_Concept
that	O
was	O
initiated	O
by	O
Microsoft	O
,	O
NCR	O
,	O
Epson	O
,	O
and	O
Fujitsu-ICL	O
and	O
is	O
managed	O
by	O
the	O
Association	O
for	O
Retail	O
Technology	O
Standards	O
.	O
</s>
<s>
The	O
OPOS	B-Library
API	O
was	O
first	O
published	O
in	O
January	O
1996	O
.	O
</s>
<s>
The	O
standard	O
uses	O
component	B-Application
object	I-Application
model	I-Application
and	O
,	O
because	O
of	O
that	O
,	O
all	O
languages	O
that	O
support	O
COM	O
controls	O
(	O
i.e.	O
</s>
<s>
Visual	B-Application
C++	I-Application
,	O
Visual	B-Language
Basic	I-Language
,	O
and	O
C#	B-Application
)	O
can	O
be	O
used	O
to	O
write	O
applications	O
.	O
</s>
<s>
The	O
OPOS	B-Library
standard	O
specifies	O
two	O
levels	O
for	O
an	O
OPOS	B-Library
control	O
,	O
the	O
control	O
object	O
which	O
presents	O
an	O
abstract	O
hardware	O
interface	O
to	O
a	O
family	O
of	O
devices	O
such	O
as	O
receipt	O
printer	O
and	O
the	O
service	O
object	O
which	O
handles	O
the	O
interface	O
between	O
the	O
control	O
object	O
and	O
the	O
actual	O
physical	O
device	O
such	O
as	O
a	O
specific	O
model	O
of	O
receipt	O
printer	O
.	O
</s>
<s>
The	O
only	O
requirement	O
is	O
that	O
a	O
hardware	O
vendor	O
supplies	O
an	O
OPOS	B-Library
compatible	O
service	O
object	O
with	O
their	O
particular	O
hardware	O
offering	O
.	O
</s>
<s>
Typically	O
a	O
manufacturer	O
of	O
point	O
of	O
sale	O
terminals	O
will	O
provide	O
along	O
with	O
a	O
terminal	O
operating	B-General_Concept
system	I-General_Concept
an	O
OPOS	B-Library
control	O
object	O
package	O
with	O
a	O
software	O
utility	O
that	O
is	O
used	O
to	O
configure	O
OPOS	B-Library
settings	O
.	O
</s>
<s>
Such	O
a	O
utility	O
will	O
specify	O
the	O
settings	O
for	O
an	O
OPOS	B-Library
control	O
object	O
and	O
indicate	O
the	O
service	O
object	O
to	O
be	O
used	O
with	O
a	O
particular	O
OPOS	B-Library
profile	O
.	O
</s>
<s>
When	O
the	O
point	O
of	O
sale	O
application	O
starts	O
up	O
,	O
it	O
loads	O
the	O
OPOS	B-Library
control	O
object	O
and	O
the	O
OPOS	B-Library
control	O
object	O
in	O
turn	O
loads	O
the	O
service	O
object	O
specified	O
by	O
the	O
current	O
OPOS	B-Library
profile	O
.	O
</s>
<s>
OPOS	B-Library
can	O
be	O
deployed	O
on	O
the	O
following	O
operating	B-General_Concept
systems	I-General_Concept
:	O
</s>
