<s>
nesC	B-Device
(	O
pronounced	O
"	O
NES-see	O
"	O
)	O
is	O
a	O
component-based	O
,	O
event-driven	B-Application
programming	I-Application
language	O
used	O
to	O
build	O
applications	O
for	O
the	O
TinyOS	B-Device
platform	O
.	O
</s>
<s>
TinyOS	B-Device
is	O
an	O
operating	B-Application
environment	I-Application
designed	O
to	O
run	O
on	O
embedded	O
devices	O
used	O
in	O
distributed	O
wireless	B-Architecture
sensor	I-Architecture
networks	I-Architecture
.	O
</s>
<s>
nesC	B-Device
is	O
built	O
as	O
an	O
extension	O
to	O
the	O
C	B-Language
programming	I-Language
language	I-Language
with	O
components	O
"	O
wired	O
"	O
together	O
to	O
run	O
applications	O
on	O
TinyOS	B-Device
.	O
</s>
<s>
The	O
name	O
nesC	B-Device
is	O
an	O
abbreviation	O
of	O
"	O
network	O
embedded	O
systems	O
C	B-Language
"	O
.	O
</s>
<s>
nesC	B-Device
programs	O
are	O
built	O
out	O
of	O
components	O
,	O
which	O
are	O
assembled	O
(	O
"	O
wired	O
"	O
)	O
to	O
form	O
whole	O
programs	O
.	O
</s>
<s>
In	O
nesC	B-Device
,	O
interfaces	O
are	O
bidirectional	O
:	O
They	O
specify	O
a	O
set	O
of	O
functions	O
to	O
be	O
implemented	O
by	O
the	O
interface	O
's	O
provider	O
(	O
commands	O
)	O
and	O
a	O
set	O
to	O
be	O
implemented	O
by	O
the	O
interface	O
's	O
user	O
(	O
events	O
)	O
.	O
</s>
<s>
This	O
is	O
critical	O
because	O
all	O
lengthy	O
commands	O
in	O
TinyOS	B-Device
(	O
e.g.	O
</s>
