<s>
40-track	B-Device
mode	I-Device
is	O
a	O
steganographic	O
technique	O
that	O
allows	O
for	O
hidden	O
data	O
on	O
a	O
3.5	O
inch	O
floppy	B-Device
diskette	I-Device
.	O
</s>
<s>
A	O
3.5	O
inch	O
720k	B-Device
diskette	B-Device
contains	O
80	O
tracks	O
,	O
9	O
sectors	O
per	O
track	O
,	O
and	O
512	O
bytes	O
per	O
sector	O
.	O
</s>
<s>
This	O
technique	O
refers	O
to	O
formatting	O
an	O
80-track	O
1.44MB	O
diskette	B-Device
as	O
a	O
special	O
40-track	O
720KB	O
diskette	B-Device
.	O
</s>
<s>
and	O
usable	O
as	O
in	O
a	O
normal	O
diskette	B-Device
,	O
and	O
the	O
latter	O
hidden	O
.	O
</s>
<s>
as	O
a	O
720KB	O
diskette	B-Device
to	O
become	O
confused	O
because	O
of	O
the	O
strange	O
data	O
in	O
between	O
even	O
numbered	O
tracks	O
.	O
</s>
