<s>
A	O
numeric	B-Device
keypad	I-Device
,	O
number	B-Device
pad	I-Device
,	O
numpad	B-Device
,	O
or	O
ten	B-Device
key	I-Device
,	O
</s>
<s>
is	O
the	O
palm-sized	O
,	O
usually-17-key	O
section	O
of	O
a	O
standard	O
computer	B-Device
keyboard	I-Device
,	O
usually	O
on	O
the	O
far	O
right	O
.	O
</s>
<s>
It	O
provides	O
calculator-style	O
efficiency	O
for	O
entering	O
numbers	O
.	O
</s>
<s>
The	O
idea	O
of	O
a	O
10-key	B-Device
number	B-Device
pad	I-Device
cluster	O
was	O
originally	O
introduced	O
by	O
Tadao	O
Kashio	O
,	O
the	O
developer	O
of	O
Casio	O
electronic	O
calculators	B-Application
.	O
</s>
<s>
The	O
numpad	B-Device
's	O
keys	O
are	O
digits	O
to	O
,	O
(	O
addition	O
)	O
,	O
(	O
subtraction	O
)	O
,	O
(	O
multiplication	O
)	O
and	O
(	O
division	O
)	O
symbols	O
,	O
(	O
decimal	O
point	O
)	O
,	O
,	O
and	O
keys	O
.	O
</s>
<s>
Laptop	B-Device
keyboards	B-Device
often	O
do	O
not	O
have	O
a	O
numpad	B-Device
,	O
but	O
may	O
provide	O
numpad	B-Device
input	O
by	O
holding	O
a	O
modifier	O
key	O
(	O
typically	O
labelled	O
)	O
and	O
operating	O
keys	O
on	O
the	O
standard	O
keyboard	B-Device
.	O
</s>
<s>
Particularly	O
large	O
laptops	B-Device
(	O
typically	O
those	O
with	O
a	O
15.6inch	O
screen	O
or	O
larger	O
)	O
may	O
have	O
space	O
for	O
a	O
real	O
numpad	B-Device
,	O
and	O
many	O
companies	O
sell	O
separate	O
numpads	B-Device
which	O
connect	O
to	O
the	O
host	O
laptop	B-Device
by	O
a	O
USB	O
connection	O
(	O
many	O
of	O
these	O
also	O
add	O
an	O
additional	O
spacebar	B-Device
off	O
to	O
the	O
side	O
of	O
the	O
zero	O
where	O
the	O
thumb	O
is	O
located	O
,	O
as	O
well	O
as	O
an	O
additional	O
key	O
typical	O
of	O
modern	O
adding	O
machines	O
and	O
cash	O
registers	O
.	O
</s>
<s>
Some	O
specialist	O
numpads	B-Device
may	O
also	O
include	O
an	O
additional	O
key	O
)	O
.	O
</s>
<s>
Sometimes	O
it	O
is	O
necessary	O
to	O
distinguish	O
between	O
a	O
key	O
on	O
the	O
numpad	B-Device
and	O
an	O
equivalent	O
key	O
elsewhere	O
on	O
the	O
keyboard	B-Device
.	O
</s>
<s>
For	O
example	O
,	O
depending	O
on	O
the	O
software	O
in	O
use	O
,	O
pressing	O
the	O
numpad	B-Device
's	O
key	O
may	O
produce	O
different	O
results	O
than	O
pressing	O
the	O
alphanumeric	O
key	O
.	O
</s>
<s>
In	O
such	O
cases	O
,	O
the	O
numpad-specific	O
key	O
may	O
be	O
indicated	O
as	O
e.g.	O
</s>
<s>
Numeric	B-Device
keypads	I-Device
usually	O
operate	O
in	O
two	O
modes	O
.	O
</s>
<s>
When	O
Num	B-Device
Lock	I-Device
is	O
off	O
,	O
keys	O
,	O
,	O
,	O
and	O
act	O
like	O
arrow/navigation	O
keys	O
up	O
,	O
right	O
,	O
down	O
,	O
and	O
left	O
;	O
and	O
,	O
,	O
,	O
and	O
act	O
like	O
,	O
,	O
,	O
and	O
,	O
respectively	O
.	O
</s>
<s>
On	O
Apple	O
Macintosh	B-Device
computers	O
,	O
which	O
lack	O
a	O
key	O
,	O
the	O
numeric	B-Device
keypad	I-Device
always	O
produces	O
only	O
numbers	O
;	O
the	O
key	O
is	O
replaced	O
by	O
the	O
.	O
</s>
<s>
The	O
arrangement	O
of	O
digits	O
on	O
numeric	B-Device
keypads	I-Device
with	O
the	O
--	O
keys	O
two	O
rows	O
above	O
the	O
--	O
keys	O
is	O
derived	O
from	O
calculators	B-Application
and	O
cash	O
registers	O
.	O
</s>
<s>
Numeric	B-Device
keypads	I-Device
are	O
useful	O
for	O
entering	O
long	O
sequences	O
of	O
numbers	O
quickly	O
,	O
for	O
example	O
in	O
spreadsheets	B-Application
,	O
financial/accounting	O
programs	O
,	O
and	O
calculators	B-Application
.	O
</s>
<s>
Input	O
in	O
this	O
style	O
is	O
similar	O
to	O
a	O
calculator	B-Application
or	O
adding	O
machine	O
.	O
</s>
<s>
A	O
numpad	B-Device
is	O
also	O
useful	O
on	O
Windows	O
PCs	O
for	O
typing	O
alt	O
codes	O
for	O
special	O
symbols	O
,	O
for	O
example	O
the	O
degree	O
symbol	O
,	O
°	O
,	O
with	O
.	O
</s>
<s>
Technically	O
,	O
the	O
previous	O
example	O
's	O
method	O
using	O
a	O
leading	O
(	O
ANSI	O
alt	O
code	O
)	O
only	O
works	O
when	O
used	O
with	O
the	O
numpad	B-Device
's	O
own	O
keys	O
,	O
so	O
it	O
could	O
be	O
written	O
less	O
ambiguously	O
(	O
if	O
necessary	O
)	O
using	O
one	O
of	O
the	O
notations	O
mentioned	O
above	O
,	O
e.g.	O
</s>
<s>
To	O
maintain	O
their	O
compact	O
size	O
,	O
Mac	O
laptops	B-Device
and	O
most	O
PC	O
notebooks	B-Device
do	O
not	O
include	O
a	O
Numeric	B-Device
Keypad	I-Device
.	O
</s>
<s>
To	O
compensate	O
it	O
,	O
most	O
PCs	O
include	O
integrated	O
into	O
a	O
function	O
key	O
(	O
typically	O
or	O
)	O
and	O
then	O
press	O
keys	O
like	O
to	O
produce	O
a	O
NumPad	B-Device
7	O
,	O
although	O
some	O
PC	O
notebooks	B-Device
do	O
not	O
include	O
such	O
shortcuts	O
.	O
</s>
<s>
Ten	B-Device
key	I-Device
speed	O
is	O
measured	O
in	O
Keystrokes	O
per	O
Hour	O
(	O
KPH	O
)	O
.	O
</s>
<s>
The	O
numeric	B-Device
keypad	I-Device
is	O
used	O
by	O
some	O
systems	O
for	O
input	O
of	O
Chinese	O
characters	O
,	O
for	O
example	O
CKC	O
Chinese	O
Input	O
System	O
and	O
Q9	O
input	O
method	O
.	O
</s>
<s>
Numeric	B-Device
keypads	I-Device
are	O
also	O
used	O
for	O
playing	O
some	O
computer	O
games	O
where	O
the	O
player	O
must	O
control	O
a	O
character	O
,	O
for	O
example	O
roguelikes	O
.	O
</s>
<s>
Unlike	O
arrow	B-Device
keys	I-Device
,	O
the	O
numeric	B-Device
keypad	I-Device
allows	O
diagonal	O
movement	O
.	O
</s>
<s>
For	O
keyboards	B-Device
without	O
a	O
numeric	B-Device
keypad	I-Device
,	O
some	O
games	O
provide	O
alternative	O
movement	B-Device
keys	I-Device
,	O
such	O
as	O
classic	O
Rogue	B-Application
's	O
HJKL	O
keys	O
.	O
</s>
<s>
The	O
numeric	B-Device
keypad	I-Device
can	O
also	O
be	O
an	O
alternative	O
to	O
the	O
WASD	O
keys	O
for	O
navigation	O
in	O
computer	O
gaming	O
.	O
</s>
<s>
This	O
can	O
be	O
an	O
attractive	O
option	O
for	O
left-handed	O
people	O
who	O
prefer	O
to	O
use	O
the	O
mouse	B-Device
with	O
their	O
left	O
hand	O
.	O
</s>
<s>
Most	O
operating	O
systems	O
have	O
a	O
mouse	B-Device
keys	O
accessibility	O
feature	O
where	O
mouse	B-Device
navigation	O
can	O
be	O
done	O
using	O
the	O
numeric	B-Device
keypad	I-Device
,	O
with	O
the	O
other	O
keys	O
adapted	O
to	O
be	O
mouse	B-Device
buttons	O
.	O
</s>
