<s>
Plans	O
are	O
a	O
set	O
of	O
drawings	B-Application
or	O
two-dimensional	O
diagrams	O
used	O
to	O
describe	O
a	O
place	O
or	O
object	O
,	O
or	O
to	O
communicate	O
building	O
or	O
fabrication	O
instructions	O
.	O
</s>
<s>
Plans	O
are	O
used	O
in	O
a	O
range	O
of	O
fields	O
:	O
architecture	O
,	O
urban	O
planning	O
,	O
landscape	O
architecture	O
,	O
mechanical	B-Application
engineering	O
,	O
civil	O
engineering	O
,	O
industrial	O
engineering	O
to	O
systems	O
engineering	O
.	O
</s>
<s>
More	O
specifically	O
a	O
plan	O
view	O
is	O
an	O
orthographic	O
projection	O
looking	O
down	O
on	O
the	O
object	O
,	O
such	O
as	O
in	O
a	O
floor	B-Application
plan	I-Application
.	O
</s>
<s>
The	O
process	O
of	O
producing	O
plans	O
,	O
and	O
the	O
skill	O
of	O
producing	O
them	O
,	O
is	O
often	O
referred	O
to	O
as	O
technical	B-Application
drawing	I-Application
.	O
</s>
<s>
A	O
working	B-Application
drawing	I-Application
is	O
a	O
type	O
of	O
technical	B-Application
drawing	I-Application
,	O
which	O
is	O
part	O
of	O
the	O
documentation	O
needed	O
to	O
build	O
an	O
engineering	O
product	O
or	O
architecture	O
.	O
</s>
<s>
Typically	O
in	O
architecture	O
these	O
could	O
include	O
civil	B-Application
drawings	I-Application
,	O
architectural	B-Architecture
drawings	I-Architecture
,	O
structural	B-Application
drawings	I-Application
,	O
mechanical	B-Application
drawings	I-Application
,	O
electrical	O
drawings	B-Application
,	O
and	O
plumbing	B-Application
drawings	I-Application
.	O
</s>
<s>
In	O
engineering	O
,	O
these	O
drawings	B-Application
show	O
all	O
necessary	O
data	O
to	O
manufacture	O
a	O
given	O
object	O
,	O
such	O
as	O
dimensions	O
and	O
angles	O
.	O
</s>
<s>
The	O
set	O
includes	O
all	O
the	O
information	O
required	O
for	O
the	O
purpose	O
of	O
the	O
set	O
,	O
and	O
may	O
exclude	O
views	B-Algorithm
or	O
projections	B-Algorithm
which	O
are	O
unnecessary	O
.	O
</s>
<s>
A	O
set	O
of	O
plans	O
can	O
also	O
take	O
the	O
form	O
of	O
a	O
digital	O
file	O
in	O
a	O
proprietary	O
format	O
such	O
as	O
DWG	O
or	O
an	O
exchange	O
file	O
format	O
such	O
as	O
DXF	O
or	O
PDF	B-Application
.	O
</s>
<s>
Plans	O
are	O
often	O
referred	O
to	O
as	O
"	O
blueprints	B-Application
"	O
or	O
"	O
bluelines	B-Application
"	O
.	O
</s>
<s>
Plans	O
are	O
usually	O
"	O
scale	B-Application
drawings	I-Application
"	O
,	O
meaning	O
that	O
the	O
plans	O
are	O
drawn	O
at	O
a	O
specific	O
ratio	O
relative	O
to	O
the	O
actual	O
size	O
of	O
the	O
place	O
or	O
object	O
.	O
</s>
<s>
Various	O
scales	O
may	O
be	O
used	O
for	O
different	O
drawings	B-Application
in	O
a	O
set	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
floor	B-Application
plan	I-Application
may	O
be	O
drawn	O
at	O
1:48	O
(	O
or	O
1/4	O
"	O
=	O
1'-0	O
"	O
)	O
whereas	O
a	O
detailed	O
view	O
may	O
be	O
drawn	O
at	O
1:24	O
(	O
or	O
1/2	O
"	O
=	O
1'-0	O
"	O
)	O
.	O
</s>
<s>
Because	O
plans	O
represent	O
three-dimensional	O
objects	O
on	O
a	O
two-dimensional	O
plane	O
,	O
the	O
use	O
of	O
views	B-Algorithm
or	O
projections	B-Algorithm
is	O
crucial	O
to	O
the	O
legibility	O
of	O
plans	O
.	O
</s>
<s>
Perspective	B-Architecture
projection	I-Architecture
,	O
including	O
:	O
</s>
<s>
Specific	O
plans	O
:	O
Floor	B-Application
plans	I-Application
,	O
starting	O
with	O
the	O
lowest	O
floor	O
and	O
ending	O
with	O
the	O
roof	O
plan	O
usually	O
appear	O
near	O
the	O
beginning	O
of	O
the	O
set	O
.	O
</s>
<s>
Further	O
,	O
for	O
example	O
,	O
reflected	O
Ceiling	O
Plans	O
(	O
RCP	O
)	O
s	O
showing	O
ceiling	O
layouts	O
appear	O
after	O
the	O
floor	B-Application
plans	I-Application
.	O
</s>
<s>
Sections	O
:	O
Building	O
sections	O
that	O
describe	O
views	B-Algorithm
cut	O
through	O
the	O
entire	O
building	O
appear	O
next	O
,	O
followed	O
by	O
wall	O
sections	O
,	O
then	O
detail	O
sections	O
.	O
</s>
<s>
These	O
details	O
may	O
also	O
include	O
millwork	O
drawings	B-Application
or	O
other	O
interior	O
details	O
.	O
</s>
<s>
Where	O
additional	O
systems	O
are	O
complex	O
and	O
require	O
many	O
details	O
for	O
installation	O
,	O
specialized	O
additional	O
plan	O
drawings	B-Application
may	O
be	O
used	O
,	O
such	O
as	O
:	O
</s>
<s>
Structural	B-Application
:	O
While	O
smaller	O
projects	O
may	O
only	O
show	O
structural	B-Application
information	O
on	O
the	O
plans	O
and	O
sections	O
,	O
larger	O
projects	O
have	O
separate	O
sheets	O
describing	O
the	O
structure	O
of	O
the	O
building	O
.	O
</s>
<s>
Mechanical	B-Application
:	O
Mechanical	B-Application
drawings	I-Application
show	O
plumbing	O
,	O
heating	O
,	O
ventilation	O
and	O
air	O
conditioning	O
systems	O
,	O
or	O
fire	O
protection	O
systems	O
.	O
</s>
<s>
Electrical	O
:Electrical	O
plan	O
drawings	B-Application
may	O
include	O
equipment	O
and	O
cable	O
tray	O
layout	O
,	O
lighting	O
and	O
power	O
,	O
grounding	O
,	O
telephone	O
,	O
local	O
area	O
network	O
,	O
special	O
communications	O
or	O
signal	O
systems	O
,	O
or	O
a	O
reflected	O
lighting	O
plan	O
.	O
</s>
