<s>
Hard	B-Architecture
sectoring	I-Architecture
in	O
a	O
magnetic	B-Architecture
or	O
optical	B-Device
data	B-General_Concept
storage	I-General_Concept
device	I-General_Concept
is	O
a	O
form	O
of	O
sectoring	O
which	O
uses	O
a	O
physical	O
mark	O
or	O
hole	O
in	O
the	O
recording	O
medium	O
to	O
reference	O
sector	B-Application
locations	O
.	O
</s>
<s>
of	O
each	O
sector	B-Application
.	O
</s>
<s>
This	O
was	O
in	O
addition	O
to	O
the	O
index	B-Architecture
hole	I-Architecture
,	O
situated	O
between	O
two	O
sector	B-Application
holes	O
,	O
to	O
mark	O
the	O
start	O
of	O
the	O
entire	O
track	O
of	O
sectors	O
.	O
</s>
<s>
When	O
the	O
index	O
or	O
sector	B-Application
hole	O
was	O
recognized	O
by	O
an	O
optical	B-Application
sensor	I-Application
,	O
a	O
sector	B-Application
signal	O
was	O
generated	O
.	O
</s>
<s>
Timing	O
electronics	O
or	O
software	O
would	O
use	O
the	O
faster	O
timing	O
of	O
the	O
index	B-Architecture
hole	I-Architecture
between	O
sector	B-Application
holes	O
,	O
to	O
generate	O
an	O
index	O
signal	O
.	O
</s>
