<s>
In	O
computer	B-General_Concept
storage	I-General_Concept
,	O
a	O
tape	B-Device
library	I-Device
,	O
sometimes	O
called	O
a	O
tape	B-Device
silo	I-Device
,	O
tape	B-Device
robot	I-Device
or	O
tape	B-Device
jukebox	I-Device
,	O
is	O
a	O
storage	O
device	O
that	O
contains	O
one	O
or	O
more	O
tape	B-Architecture
drives	O
,	O
a	O
number	O
of	O
slots	O
to	O
hold	O
tape	B-Architecture
cartridges	O
,	O
a	O
barcode	O
reader	O
to	O
identify	O
tape	B-Architecture
cartridges	O
and	O
an	O
automated	O
method	O
for	O
loading	O
tapes	O
(	O
a	O
robot	O
)	O
.	O
</s>
<s>
Additionally	O
,	O
the	O
area	O
where	O
tapes	O
that	O
are	O
NOT	O
currently	O
in	O
a	O
silo	O
are	O
stored	O
is	O
also	O
called	O
a	O
tape	B-Device
library	I-Device
.	O
</s>
<s>
Tape	B-Device
libraries	I-Device
can	O
contain	O
millions	O
of	O
tapes	O
.	O
</s>
<s>
One	O
of	O
the	O
earliest	O
examples	O
was	O
the	O
IBM	B-Device
3850	I-Device
Mass	I-Device
Storage	I-Device
System	I-Device
(	O
MSS	O
)	O
,	O
announced	O
in	O
1974	O
.	O
</s>
<s>
Such	O
capacity	O
is	O
multiple	O
thousand	O
times	O
that	O
of	O
a	O
typical	O
hard	B-Device
drive	I-Device
and	O
well	O
in	O
excess	O
of	O
what	O
is	O
capable	O
with	O
network	B-Application
attached	I-Application
storage	I-Application
.	O
</s>
<s>
Because	O
of	O
their	O
slow	O
sequential	O
access	O
and	O
huge	O
capacity	O
,	O
tape	B-Device
libraries	I-Device
are	O
primarily	O
used	O
for	O
backups	B-Protocol
and	O
as	O
the	O
final	O
stage	O
of	O
digital	O
archiving	O
.	O
</s>
<s>
Another	O
example	O
is	O
hierarchical	B-Application
storage	I-Application
management	I-Application
(	O
HSM	O
)	O
,	O
in	O
which	O
tape	B-Device
library	I-Device
is	O
used	O
to	O
hold	O
rarely	O
used	O
files	O
from	O
file	B-Application
systems	I-Application
.	O
</s>
<s>
Open-Source	O
support	O
includes	O
AMANDA	B-Application
and	O
the	O
minimal	O
mtx	O
program	O
.	O
</s>
<s>
Tape	B-Device
libraries	I-Device
commonly	O
have	O
the	O
capability	O
of	O
optically	O
scanning	O
barcode	O
labels	O
which	O
are	O
attached	O
to	O
each	O
tape	B-Architecture
,	O
allowing	O
them	O
to	O
automatically	O
maintain	O
an	O
inventory	O
of	O
which	O
tapes	O
are	O
where	O
within	O
the	O
library	O
.	O
</s>
<s>
The	O
barcode	O
label	O
is	O
frequently	O
part	O
of	O
the	O
tape	B-Device
label	I-Device
,	O
information	O
recorded	O
at	O
the	O
beginning	O
of	O
the	O
medium	O
to	O
uniquely	O
identify	O
the	O
tape	B-Architecture
.	O
</s>
<s>
Smaller	O
tape	B-Device
libraries	I-Device
with	O
only	O
one	O
drive	O
are	O
known	O
as	O
autoloaders	O
.	O
</s>
<s>
Other	O
types	O
of	O
autoloaders	O
may	O
operate	O
with	O
optical	B-Device
discs	I-Device
(	O
such	O
as	O
compact	O
discs	O
or	O
DVDs	O
)	O
or	O
floppy	B-Device
disks	I-Device
.	O
</s>
