<s>
More	O
generally	O
,	O
to	O
write	O
a	O
number	O
in	O
the	O
form	O
a	O
×	O
10b	O
,	O
where	O
1	O
<	O
a	O
<	O
10	O
and	O
b	O
is	O
an	O
integer	O
,	O
is	O
to	O
express	O
it	O
in	O
scientific	O
notation	O
,	O
and	O
a	O
is	O
called	O
the	O
significand	B-Algorithm
or	O
the	O
mantissa	B-Algorithm
,	O
and	O
b	O
is	O
its	O
exponent	O
.	O
</s>
<s>
Decades	O
are	O
especially	O
useful	O
when	O
describing	O
frequency	O
response	O
of	O
electronic	O
systems	O
,	O
such	O
as	O
audio	O
amplifiers	O
and	O
filters	B-Architecture
.	O
</s>
<s>
How	O
many	O
decades	O
is	O
one	O
octave	B-Language
?	O
</s>
<s>
Decades	O
on	O
a	O
logarithmic	O
scale	O
,	O
rather	O
than	O
unit	O
steps	O
(	O
steps	O
of	O
1	O
)	O
or	O
other	O
linear	O
scale	O
,	O
are	O
commonly	O
used	O
on	O
the	O
horizontal	O
axis	O
when	O
representing	O
the	O
frequency	O
response	O
of	O
electronic	O
circuits	O
in	O
graphical	O
form	O
,	O
such	O
as	O
in	O
Bode	B-Algorithm
plots	I-Algorithm
,	O
since	O
depicting	O
large	O
frequency	O
ranges	O
on	O
a	O
linear	O
scale	O
is	O
often	O
not	O
practical	O
.	O
</s>
<s>
The	O
example	O
Bode	B-Algorithm
plot	I-Algorithm
shows	O
a	O
slope	O
of	O
−	O
20dB/decade	O
in	O
the	O
stopband	O
,	O
which	O
means	O
that	O
for	O
every	O
factor-of-ten	O
increase	O
in	O
frequency	O
(	O
going	O
from	O
10	O
rad/s	O
to	O
100	O
rad/s	O
in	O
the	O
figure	O
)	O
,	O
the	O
gain	O
decreases	O
by	O
20dB	O
.	O
</s>
