<s>
In	O
computer	B-General_Concept
science	I-General_Concept
and	O
software	B-General_Concept
engineering	I-General_Concept
,	O
reusability	B-Application
is	O
the	O
use	O
of	O
existing	O
assets	O
in	O
some	O
form	O
within	O
the	O
software	O
product	O
development	O
process	O
;	O
these	O
assets	O
are	O
products	O
and	O
by-products	O
of	O
the	O
software	O
development	O
life	O
cycle	O
and	O
include	O
code	O
,	O
software	O
components	O
,	O
test	O
suites	O
,	O
designs	O
and	O
documentation	O
.	O
</s>
<s>
The	O
opposite	O
concept	O
of	O
reusability	B-Application
is	O
leverage	O
,	O
which	O
modifies	O
existing	O
assets	O
as	O
needed	O
to	O
meet	O
specific	O
system	O
requirements	O
.	O
</s>
<s>
A	O
chunk	O
of	O
code	O
is	O
regularly	O
organized	O
using	O
modules	B-Architecture
or	O
namespaces	O
into	O
layers	O
.	O
</s>
<s>
Proponents	O
claim	O
that	O
objects	O
and	O
software	O
components	O
offer	O
a	O
more	O
advanced	O
form	O
of	O
reusability	B-Application
,	O
although	O
it	O
has	O
been	O
tough	O
to	O
objectively	O
measure	O
and	O
define	O
levels	O
or	O
scores	O
of	O
reusability	B-Application
.	O
</s>
<s>
Reusability	B-Application
is	O
often	O
a	O
required	O
characteristic	O
of	O
platform	B-Device
software	O
.	O
</s>
<s>
Reusability	B-Application
brings	O
several	O
aspects	O
to	O
software	O
development	O
that	O
do	O
not	O
need	O
to	O
be	O
considered	O
when	O
reusability	B-Application
is	O
not	O
required	O
.	O
</s>
<s>
Reusability	B-Application
implies	O
some	O
explicit	O
management	O
of	O
build	O
,	O
packaging	B-Algorithm
,	O
distribution	O
,	O
installation	B-Application
,	O
configuration	B-General_Concept
,	O
deployment	B-Application
,	O
maintenance	O
and	O
upgrade	B-General_Concept
issues	O
.	O
</s>
<s>
Software	B-Application
reusability	I-Application
more	O
specifically	O
refers	O
to	O
design	O
features	O
of	O
a	O
software	O
element	O
(	O
or	O
collection	O
of	O
software	O
elements	O
)	O
that	O
enhance	O
its	O
suitability	O
for	O
reuse	O
.	O
</s>
