<s>
IMG	B-General_Concept
,	O
in	O
computing	O
,	O
refers	O
to	O
binary	O
files	O
with	O
the	O
.img	B-General_Concept
filename	O
extension	O
that	O
store	O
raw	O
disk	B-Application
images	I-Application
of	O
floppy	B-Device
disks	I-Device
,	O
hard	B-Device
drives	I-Device
,	O
and	O
optical	B-Device
discs	I-Device
or	O
a	O
bitmap	O
image	O
–	O
.img	B-General_Concept
.	O
</s>
<s>
The	O
.img	B-General_Concept
filename	O
extension	O
is	O
used	O
by	O
disk	B-Application
image	I-Application
files	O
,	O
which	O
contain	O
raw	O
dumps	O
of	O
a	O
magnetic	B-Device
disk	I-Device
or	O
of	O
an	O
optical	B-Device
disc	I-Device
.	O
</s>
<s>
Since	O
a	O
raw	O
image	O
consists	O
of	O
a	O
sector-by-sector	O
binary	O
copy	O
of	O
the	O
source	O
medium	O
,	O
the	O
actual	O
format	O
of	O
the	O
file	O
contents	O
will	O
depend	O
on	O
the	O
file	B-Application
system	I-Application
of	O
the	O
disk	B-Device
from	O
which	O
the	O
image	O
was	O
created	O
(	O
such	O
as	O
a	O
version	O
of	O
FAT	B-Application
)	O
.	O
</s>
<s>
Raw	O
disk	B-Application
images	I-Application
of	O
optical	B-Device
media	I-Device
(	O
such	O
as	O
CDs	B-Device
and	O
DVDs	O
)	O
contain	O
a	O
raw	O
image	O
of	O
all	O
the	O
tracks	O
in	O
a	O
disc	O
(	O
which	O
can	O
include	O
audio	O
,	O
data	O
and	O
video	O
tracks	O
)	O
.	O
</s>
<s>
In	O
the	O
case	O
of	O
CD-ROMs	B-Device
and	O
DVDs	O
,	O
these	O
images	O
usually	O
include	O
not	O
only	O
the	O
data	O
from	O
each	O
sector	B-Application
,	O
but	O
the	O
control	O
headers	O
and	O
error	O
correction	O
fields	O
for	O
each	O
sector	B-Application
as	O
well	O
.	O
</s>
<s>
Since	O
IMG	B-General_Concept
files	I-General_Concept
hold	O
no	O
additional	O
data	O
beyond	O
the	O
disk	B-Device
contents	O
,	O
these	O
files	O
can	O
only	O
be	O
automatically	O
handled	O
by	O
programs	O
that	O
can	O
detect	O
their	O
file	B-Application
systems	I-Application
.	O
</s>
<s>
For	O
instance	O
,	O
a	O
typical	O
raw	O
disk	B-Application
image	I-Application
of	O
a	O
floppy	B-Device
disk	I-Device
begins	O
with	O
a	O
FAT	B-Application
boot	O
sector	B-Application
,	O
which	O
can	O
be	O
used	O
to	O
identify	O
its	O
file	B-Application
system	I-Application
.	O
</s>
<s>
Disc	B-Application
images	I-Application
of	O
optical	B-Device
media	I-Device
are	O
usually	O
accompanied	O
by	O
a	O
descriptor	O
file	O
which	O
describes	O
the	O
layout	O
of	O
the	O
disc	O
,	O
and	O
includes	O
information	O
such	O
as	O
track	O
limits	O
which	O
are	O
not	O
stored	O
in	O
the	O
raw	O
image	O
file	O
.	O
</s>
<s>
The	O
.img	B-General_Concept
file	I-General_Concept
extension	O
was	O
originally	O
used	O
for	O
floppy	B-Device
disk	I-Device
raw	O
disk	B-Application
images	I-Application
only	O
.	O
</s>
<s>
A	O
similar	O
file	O
extension	O
,	O
.ima	B-General_Concept
,	O
is	O
also	O
used	O
to	O
refer	O
to	O
floppy	B-Device
disk	I-Device
image	O
files	O
by	O
some	O
programs	O
.	O
</s>
<s>
A	O
variant	O
of	O
IMG	B-General_Concept
,	O
called	O
IMZ	O
,	O
consists	O
of	O
a	O
gzipped	O
version	O
of	O
a	O
raw	O
floppy	B-Device
disk	I-Device
image	O
.	O
</s>
<s>
These	O
files	O
use	O
the	O
.imz	O
file	O
extension	O
,	O
and	O
are	O
commonly	O
found	O
in	O
compressed	O
images	O
of	O
floppy	B-Device
disks	I-Device
created	O
by	O
WinImage	O
.	O
</s>
<s>
QEMU	B-Application
uses	O
the	O
.img	B-General_Concept
file	I-General_Concept
extension	O
for	O
raw	O
images	O
of	O
hard	B-Device
drive	I-Device
disks	B-Device
,	O
calling	O
the	O
format	O
simply	O
"	O
raw	O
"	O
.	O
</s>
<s>
CloneCD	B-Application
stores	O
optical	B-General_Concept
disc	I-General_Concept
images	I-General_Concept
in	O
.img	B-General_Concept
files	I-General_Concept
and	O
generates	O
additional	O
CloneCD	B-Application
Control	O
Files	O
(	O
with	O
.ccd	O
extension	O
)	O
for	O
each	O
image	O
to	O
hold	O
the	O
necessary	O
metadata	O
.	O
</s>
<s>
The	O
CUE/BIN	O
format	O
stores	O
disc	B-Application
images	I-Application
in	O
.bin	O
files	O
,	O
which	O
are	O
functionally	O
equivalent	O
to	O
.img	B-General_Concept
image	O
files	O
,	O
and	O
uses	O
.cue	O
files	O
as	O
descriptor	O
files	O
.	O
</s>
<s>
The	O
file	O
size	O
of	O
a	O
raw	O
disk	B-Application
image	I-Application
is	O
always	O
a	O
multiple	O
of	O
the	O
sector	B-Application
size	O
.	O
</s>
<s>
For	O
floppy	B-Device
disks	I-Device
and	O
hard	B-Device
drives	I-Device
this	O
size	O
is	O
typically	O
512	B-Application
bytes	I-Application
(	O
but	O
other	O
sizes	O
such	O
as	O
128	O
and	O
1024	O
exist	O
)	O
.	O
</s>
<s>
More	O
precisely	O
,	O
the	O
file	O
size	O
of	O
a	O
raw	O
disk	B-Application
image	I-Application
of	O
a	O
magnetic	B-Device
disk	I-Device
corresponds	O
to	O
:	O
</s>
<s>
For	O
optical	B-Device
discs	I-Device
such	O
as	O
CDs	B-Device
and	O
DVDs	O
,	O
the	O
raw	O
sector	B-Application
size	O
is	O
usually	O
2	O
,	O
352	O
,	O
making	O
the	O
size	O
of	O
a	O
raw	O
disc	B-Application
image	I-Application
a	O
multiple	O
of	O
this	O
value	O
.	O
</s>
<s>
ISO	B-General_Concept
images	I-General_Concept
are	O
another	O
type	O
of	O
optical	B-General_Concept
disc	I-General_Concept
image	I-General_Concept
files	O
,	O
which	O
commonly	O
use	O
the	O
.iso	B-General_Concept
file	I-General_Concept
extension	O
,	O
but	O
sometimes	O
use	O
the	O
.img	B-General_Concept
file	I-General_Concept
extension	O
as	O
well	O
.	O
</s>
<s>
They	O
are	O
similar	O
to	O
the	O
raw	O
optical	B-General_Concept
disc	I-General_Concept
images	I-General_Concept
,	O
but	O
contain	O
only	O
one	O
track	O
with	O
computer	O
data	O
obtained	O
from	O
an	O
optical	B-Device
disc	I-Device
.	O
</s>
<s>
They	O
also	O
do	O
not	O
contain	O
the	O
control	O
headers	O
and	O
error	O
correction	O
fields	O
of	O
CD-ROM	B-Device
or	O
DVD	O
sectors	O
that	O
raw	O
disc	B-Application
images	I-Application
usually	O
store	O
.	O
</s>
<s>
Their	O
internal	O
format	O
follows	O
the	O
structure	O
of	O
an	O
optical	B-Device
disc	I-Device
file	B-Application
system	I-Application
,	O
commonly	O
ISO	B-Application
9660	I-Application
(	O
for	O
CDs	B-Device
)	O
or	O
UDF	O
(	O
for	O
DVDs	O
)	O
.	O
</s>
<s>
The	O
CUE/BIN	O
and	O
CCD/IMG	O
formats	O
,	O
which	O
usually	O
contain	O
raw	O
disc	B-Application
images	I-Application
,	O
can	O
also	O
store	O
ISO	B-General_Concept
images	I-General_Concept
instead	O
.	O
</s>
<s>
.img	B-General_Concept
is	O
also	O
a	O
planar	O
bitmap	O
graphics	O
file	O
using	O
simple	O
run-length	O
encoding	O
,	O
originating	O
with	O
Digital	O
Research	O
's	O
GEM	B-Application
.	O
</s>
<s>
It	O
was	O
commonly	O
used	O
on	O
the	O
Atari	B-Device
ST	I-Device
line	O
of	O
home	O
computers	O
,	O
but	O
also	O
with	O
some	O
GEM-based	O
PC	O
software	O
such	O
as	O
Corel	B-Application
Ventura	I-Application
or	O
Timeworks	B-Application
Publisher	I-Application
.	O
</s>
<s>
In	O
addition	O
,	O
.img	B-General_Concept
is	O
an	O
Apple	B-Operating_System
Disk	I-Operating_System
Image	I-Operating_System
used	O
by	O
the	O
Mac	B-Application
OS	I-Application
X	O
or	O
macOS	B-Application
operating	O
system	O
.	O
</s>
<s>
Garmin	O
.img	B-General_Concept
is	O
a	O
hard-disk	B-Device
image	O
file	O
format	O
which	O
contains	O
a	O
header	O
and	O
many	O
subfiles	O
and	O
used	O
to	O
store	O
the	O
maps	O
for	O
its	O
GPS	O
units	O
.	O
</s>
<s>
The	O
raw	O
IMG	B-General_Concept
file	I-General_Concept
format	O
is	O
used	O
by	O
several	O
tools	O
:	O
</s>
<s>
RaWrite	O
and	O
WinImage	O
use	O
the	O
IMG	B-General_Concept
disk	B-Application
image	I-Application
format	O
to	O
read	O
and	O
write	O
floppy	B-Device
disk	I-Device
images	O
.	O
</s>
<s>
ImDisk	O
and	O
can	O
mount	O
a	O
raw	O
image	O
of	O
a	O
floppy	B-Device
disk	I-Device
to	O
emulate	O
a	O
floppy	B-Device
drive	I-Device
under	O
Microsoft	B-Application
Windows	I-Application
.	O
</s>
<s>
Nero	B-Application
Burning	I-Application
ROM	I-Application
supports	O
reading	O
IMG	B-General_Concept
files	I-General_Concept
for	O
creating	O
bootable	O
CDs	B-Device
.	O
</s>
<s>
mtools	B-Application
allows	O
manipulation	O
of	O
MS-DOS	B-Application
floppy	B-Device
disk	I-Device
images	O
in	O
Unix	B-Application
systems	I-Application
.	O
</s>
<s>
Programs	O
such	O
as	O
dsktrans	O
from	O
the	O
LibDsk	O
suite	O
of	O
command-line	O
tools	O
(	O
available	O
for	O
Linux	B-Application
,	O
MS-DOS	B-Application
,	O
and	O
Microsoft	B-Application
Windows	I-Application
)	O
will	O
convert	O
between	O
different	O
raw	O
disk	B-Application
image	I-Application
formats	O
.	O
</s>
<s>
dd	B-Application
can	O
be	O
used	O
in	O
Unix	B-Application
to	O
create	O
raw	O
disk	B-Application
image	I-Application
files	O
of	O
disks	B-Device
.	O
</s>
<s>
QEMU	B-Application
uses	O
IMG	B-General_Concept
files	I-General_Concept
as	O
its	O
default	O
format	O
for	O
hard	B-Device
drive	I-Device
disk	B-Application
images	I-Application
.	O
</s>
<s>
IrfanView	B-Protocol
with	O
the	O
plugin	O
"	O
FORMATS	O
"	O
(	O
formats.dll	O
)	O
supports	O
viewing	O
GEM-IMG	O
vector	O
graphics	O
.	O
</s>
<s>
Garmin	O
MapSource	O
or	O
GPSMapEdit	O
can	O
be	O
used	O
to	O
read	O
Garmin	O
hard-disk	B-Device
image	O
.img	B-General_Concept
format	O
.	O
</s>
