<s>
Data	B-General_Concept
storage	I-General_Concept
is	O
the	O
recording	O
(	O
storing	O
)	O
of	O
information	O
(	O
data	O
)	O
in	O
a	O
storage	B-General_Concept
medium	I-General_Concept
.	O
</s>
<s>
Handwriting	O
,	O
phonographic	O
recording	O
,	O
magnetic	O
tape	O
,	O
and	O
optical	B-Device
discs	I-Device
are	O
all	O
examples	O
of	O
storage	B-General_Concept
media	I-General_Concept
.	O
</s>
<s>
Biological	O
molecules	O
such	O
as	O
RNA	O
and	O
DNA	O
are	O
considered	O
by	O
some	O
as	O
data	B-General_Concept
storage	I-General_Concept
.	O
</s>
<s>
Electronic	O
data	B-General_Concept
storage	I-General_Concept
requires	O
electrical	O
power	O
to	O
store	O
and	O
retrieve	O
data	O
.	O
</s>
<s>
Data	B-General_Concept
storage	I-General_Concept
in	O
a	O
digital	O
,	O
machine-readable	O
medium	O
is	O
sometimes	O
called	O
digital	O
data	O
.	O
</s>
<s>
Computer	B-General_Concept
data	I-General_Concept
storage	I-General_Concept
is	O
one	O
of	O
the	O
core	O
functions	O
of	O
a	O
general-purpose	O
computer	O
.	O
</s>
<s>
Electronic	B-Protocol
documents	I-Protocol
can	O
be	O
stored	O
in	O
much	O
less	O
space	O
than	O
paper	O
documents	O
.	O
</s>
<s>
Newly	O
created	O
information	O
is	O
distributed	O
and	O
can	O
be	O
stored	O
in	O
four	O
storage	B-General_Concept
media	I-General_Concept
–	O
print	O
,	O
film	O
,	O
magnetic	O
,	O
and	O
optical	O
–	O
and	O
seen	O
or	O
heard	O
in	O
four	O
information	O
flows	O
–	O
telephone	O
,	O
radio	O
and	O
TV	O
,	O
and	O
the	O
Internet	O
as	O
well	O
as	O
being	O
observed	O
directly	O
.	O
</s>
<s>
Digital	O
information	O
is	O
stored	O
on	O
electronic	O
media	O
in	O
many	O
different	O
recording	B-Device
formats	I-Device
.	O
</s>
<s>
With	O
electronic	O
media	O
,	O
the	O
data	O
and	O
the	O
recording	B-General_Concept
media	I-General_Concept
are	O
sometimes	O
referred	O
to	O
as	O
"	O
software	O
"	O
despite	O
the	O
more	O
common	O
use	O
of	O
the	O
word	O
to	O
describe	O
computer	O
software	O
.	O
</s>
<s>
Some	O
recording	B-General_Concept
media	I-General_Concept
may	O
be	O
temporary	O
either	O
by	O
design	O
or	O
by	O
nature	O
.	O
</s>
<s>
A	O
2003	O
UC	O
Berkeley	O
report	O
estimated	O
that	O
about	O
five	O
exabytes	O
of	O
new	O
information	O
were	O
produced	O
in	O
2002	O
and	O
that	O
92%	O
of	O
this	O
data	O
was	O
stored	O
on	O
hard	O
disk	B-Device
drives	I-Device
.	O
</s>
<s>
The	O
researchers	O
 '	O
highest	O
estimate	O
for	O
the	O
growth	O
rate	O
of	O
newly	O
stored	O
information	O
(	O
uncompressed	B-General_Concept
)	O
was	O
more	O
than	O
30%	O
per	O
year	O
.	O
</s>
<s>
A	O
2011	O
Science	O
(	O
journal	O
)	O
article	O
estimated	O
that	O
the	O
year	O
2002	O
was	O
the	O
beginning	O
of	O
the	O
digital	O
age	O
for	O
information	B-General_Concept
storage	I-General_Concept
:	O
an	O
age	O
in	O
which	O
more	O
information	O
is	O
stored	O
on	O
digital	B-General_Concept
storage	I-General_Concept
devices	O
than	O
on	O
analog	O
storage	O
devices	O
.	O
</s>
<s>
These	O
figures	O
correspond	O
to	O
less	O
than	O
three	O
compressed	B-General_Concept
exabytes	O
in	O
1986	O
,	O
and	O
295	O
compressed	B-General_Concept
exabytes	O
in	O
2007	O
.	O
</s>
<s>
The	O
quantity	O
of	O
digital	B-General_Concept
storage	I-General_Concept
doubled	O
roughly	O
every	O
three	O
years	O
.	O
</s>
<s>
In	O
a	O
more	O
limited	O
study	O
,	O
the	O
International	O
Data	O
Corporation	O
estimated	O
that	O
the	O
total	O
amount	O
of	O
digital	O
data	O
in	O
2007	O
was	O
281	O
exabytes	O
,	O
and	O
that	O
the	O
total	O
amount	O
of	O
digital	O
data	O
produced	O
exceeded	O
the	O
global	O
storage	B-General_Concept
capacity	I-General_Concept
for	O
the	O
first	O
time	O
.	O
</s>
