<s>
Virtual	B-Application
disk	I-Application
and	I-Application
virtual	I-Application
drive	I-Application
are	O
software	O
components	O
that	O
emulate	B-Application
an	O
actual	O
disk	B-Device
storage	I-Device
device	O
.	O
</s>
<s>
Virtual	B-Application
disks	I-Application
and	O
virtual	B-Application
drives	I-Application
are	O
common	O
components	O
of	O
virtual	B-Architecture
machines	I-Architecture
in	O
hardware	B-General_Concept
virtualization	I-General_Concept
,	O
but	O
they	O
are	O
also	O
widely	O
used	O
for	O
various	O
purposes	O
unrelated	O
to	O
virtualization	O
,	O
such	O
as	O
for	O
the	O
creation	O
of	O
logical	B-General_Concept
disks	I-General_Concept
.	O
</s>
<s>
A	O
virtual	B-Application
drive	I-Application
is	O
a	O
software	O
component	O
that	O
emulates	B-Application
an	O
actual	O
disk	B-Device
drive	I-Device
,	O
such	O
as	O
an	O
optical	O
disc	B-Device
drive	I-Device
,	O
a	O
floppy	B-Device
disk	I-Device
drive	I-Device
,	O
or	O
a	O
hard	B-Device
disk	I-Device
drive	I-Device
.	O
</s>
<s>
To	O
other	O
programs	O
,	O
a	O
virtual	B-Application
drive	I-Application
looks	O
and	O
behaves	O
like	O
an	O
actual	O
physical	O
device	O
.	O
</s>
<s>
A	O
virtual	B-Application
disk	I-Application
may	O
be	O
in	O
any	O
of	O
the	O
following	O
forms	O
:	O
</s>
<s>
In	O
hardware	B-General_Concept
virtualization	I-General_Concept
,	O
virtual	B-Architecture
machines	I-Architecture
implement	O
virtual	B-Application
drives	I-Application
as	O
part	O
of	O
their	O
efforts	O
to	O
emulate	B-Application
the	O
behavior	O
of	O
an	O
actual	O
machine	O
.	O
</s>
<s>
As	O
with	O
an	O
ordinary	O
computer	O
,	O
a	O
virtual	B-Architecture
machine	I-Architecture
needs	O
one	O
virtual	B-Application
drive	I-Application
and	O
one	O
disk	B-Application
image	I-Application
to	O
start	B-Operating_System
up	I-Operating_System
,	O
except	O
when	O
it	O
is	O
performing	O
a	O
network	B-Device
boot	I-Device
.	O
</s>
<s>
More	O
virtual	B-Application
drives	I-Application
are	O
added	O
as	O
needed	O
.	O
</s>
<s>
Virtual	O
optical	O
drives	O
are	O
used	O
on	O
physical	O
computers	O
to	O
transfer	O
the	O
contents	O
of	O
the	O
optical	O
disks	B-Device
onto	O
hard	B-Device
disk	I-Device
drives	I-Device
.	O
</s>
<s>
Doing	O
so	O
helps	O
in	O
resolving	O
the	O
problem	O
of	O
the	O
short	O
life	O
span	O
of	O
CDs	O
and	O
DVDs	O
and	O
takes	O
advantage	O
of	O
the	O
faster	O
data	O
transfer	O
rate	O
of	O
hard	B-Device
disk	I-Device
drives	I-Device
.	O
</s>
<s>
Modern	O
video	O
games	O
have	O
migrated	O
to	O
online	O
product	B-License
activation	I-License
as	O
part	O
of	O
their	O
distribution	O
process	O
.	O
</s>
