<s>
In	O
computing	O
,	O
a	O
stylus	B-Device
(	O
or	O
stylus	B-Device
pen	O
)	O
is	O
a	O
small	O
pen-shaped	O
instrument	O
whose	O
tip	O
position	O
on	O
a	O
computer	B-Device
monitor	I-Device
can	O
be	O
detected	O
.	O
</s>
<s>
While	O
devices	O
with	O
touchscreens	B-Device
such	O
as	O
newer	O
computers	O
,	O
mobile	B-Application
devices	I-Application
(	O
smartphones	B-Application
and	O
personal	B-Application
digital	I-Application
assistants	I-Application
)	O
,	O
game	O
consoles	O
,	O
and	O
graphics	B-Device
tablets	I-Device
can	O
usually	O
be	O
operated	O
with	O
a	O
fingertip	O
,	O
a	O
stylus	B-Device
provides	O
more	O
accurate	O
and	O
controllable	O
input	O
.	O
</s>
<s>
The	O
stylus	B-Device
has	O
the	O
same	O
function	O
as	O
a	O
mouse	B-Device
or	O
touchpad	B-Application
as	O
a	O
pointing	B-Device
device	I-Device
;	O
its	O
use	O
is	O
commonly	O
called	O
pen	O
computing	O
.	O
</s>
<s>
The	O
earliest	O
computer-related	O
usage	O
for	O
a	O
stylus	B-Device
was	O
in	O
1643	O
with	O
Pascal	O
's	O
calculator	O
.	O
</s>
<s>
A	O
stylus	B-Device
was	O
used	O
to	O
turn	O
the	O
dials	O
.	O
</s>
<s>
The	O
Addiator	O
was	O
a	O
pocket	O
mechanical	O
adding	O
machine	O
that	O
used	O
a	O
stylus	B-Device
to	O
move	O
tiny	O
rigid	O
slices	O
of	O
sheet-metal	O
that	O
were	O
enclosed	O
in	O
a	O
case	O
.	O
</s>
<s>
The	O
first	O
use	O
of	O
a	O
stylus	B-Device
in	O
an	O
electronic	O
computing	O
device	O
was	O
the	O
Stylator	O
,	O
demonstrated	O
by	O
Tom	O
Dimond	O
in	O
1957	O
.	O
</s>
<s>
Different	O
types	O
of	O
stylus	B-Device
are	O
used	O
for	O
graphics	B-Device
tablets	I-Device
,	O
as	O
well	O
as	O
resistive	B-Device
and	O
capacitive	O
touchscreens	B-Device
.	O
</s>
<s>
Capacitive	O
screens	O
are	O
very	O
widely	O
used	O
on	O
smart	B-Application
phones	I-Application
and	O
multi-touch	B-Application
surfaces	I-Application
,	O
where	O
simultaneous	O
use	O
of	O
several	O
fingers	O
is	O
detected	O
;	O
a	O
stylus	B-Device
cannot	O
replicate	O
this	O
.	O
</s>
<s>
Capacitive	O
(	O
also	O
called	O
passive	O
)	O
styluses	O
emulate	O
a	O
finger	O
by	O
using	O
a	O
tip	O
made	O
of	O
rubber	O
or	O
conductive	B-Algorithm
foam	I-Algorithm
;	O
or	O
metal	O
such	O
as	O
copper	O
.	O
</s>
<s>
They	O
do	O
not	O
need	O
to	O
be	O
powered	O
and	O
can	O
be	O
used	O
on	O
any	O
multi-touch	B-Application
surface	O
that	O
a	O
finger	O
can	O
be	O
used	O
,	O
typically	O
capacitive	O
screens	O
that	O
are	O
common	O
in	O
smart	B-Application
phones	I-Application
and	O
tablet	B-Device
computers	I-Device
.	O
</s>
<s>
Stylus	B-Device
tips	O
made	O
of	O
rubber	O
or	O
foam	O
are	O
often	O
large	O
,	O
making	O
it	O
rather	O
difficult	O
to	O
get	O
precise	O
notes	O
or	O
drawings	O
.	O
</s>
<s>
Screens	O
that	O
receive	O
input	O
from	O
a	O
capacitive	O
stylus	B-Device
(	O
as	O
well	O
as	O
human	O
fingers	O
)	O
ca	O
n't	O
register	O
pressure	O
applied	O
by	O
the	O
pen	O
;	O
tilting	O
of	O
the	O
pen	O
;	O
and	O
ca	O
n't	O
distinguish	O
between	O
a	O
capacitive	O
stylus	B-Device
,	O
your	O
finger	O
,	O
or	O
a	O
resting	O
palm	O
as	O
input	O
-	O
it	O
will	O
register	O
all	O
of	O
these	O
touches	O
as	O
marks	O
on	O
the	O
screen	O
.	O
</s>
<s>
Being	O
free	O
of	O
any	O
digital	B-Device
components	O
,	O
capacitive	O
styluses	O
can	O
be	O
cost	O
effective	O
to	O
manufacture	O
.	O
</s>
<s>
Capacitive	O
styluses	O
tend	O
to	O
work	O
on	O
any	O
multi-touch	B-Application
surface	O
that	O
accepts	O
input	O
from	O
a	O
finger	O
.	O
</s>
<s>
Active	O
(	O
also	O
called	O
digital	B-Device
)	O
styluses	O
include	O
digital	B-Device
components	O
or	O
circuitry	O
inside	O
the	O
pen	O
that	O
communicates	O
with	O
a	O
digitizer	O
on	O
the	O
touch	O
device	O
.	O
</s>
<s>
In	O
order	O
for	O
an	O
active	O
stylus	B-Device
to	O
function	O
,	O
its	O
digital	B-Device
component	O
protocol	O
must	O
match	O
the	O
digitizer	O
technology	O
in	O
the	O
touch	B-Device
screen	I-Device
it	O
is	O
interacting	O
with	O
.	O
</s>
<s>
Active	O
styluses	O
use	O
different	O
protocols	O
by	O
different	O
manufacturers	O
in	O
order	O
to	O
communicate	O
with	O
the	O
digitizer	O
of	O
a	O
graphic	B-Device
tablet	I-Device
or	O
multi-touch	B-Application
device	O
.	O
</s>
<s>
The	O
digital	B-Device
protocol	O
of	O
the	O
pen	O
must	O
match	O
the	O
device	O
digitizer	O
,	O
otherwise	O
input	O
from	O
the	O
pen	O
will	O
not	O
register	O
on	O
the	O
device	O
.	O
</s>
<s>
Common	O
active	O
stylus	B-Device
protocols	O
are	O
:	O
</s>
<s>
A	O
stylus	B-Device
 '	O
performance	O
is	O
measured	O
by	O
these	O
four	O
characteristics	O
:	O
</s>
<s>
Palm	O
rejection	O
or	O
detection	O
,	O
which	O
prevents	O
a	O
touch	O
device	O
from	O
registering	O
or	O
marking	O
the	O
screen	O
when	O
a	O
hand	O
or	O
palm	O
is	O
resting	O
on	O
the	O
screen	O
surface	O
,	O
relies	O
on	O
a	O
combination	O
of	O
technology	O
in	O
the	O
stylus	B-Device
,	O
the	O
OS	O
software	O
and	O
the	O
screen	O
digitizer	O
technology	O
,	O
to	O
work	O
effectively	O
.	O
</s>
<s>
A	O
stylus	B-Device
 '	O
performance	O
is	O
measured	O
by	O
these	O
four	O
characteristics	O
:	O
</s>
<s>
Smartphone	B-Application
stylus	B-Device
pens	O
have	O
become	O
a	O
popular	O
tool	O
for	O
smartphone	B-Application
users	O
who	O
want	O
to	O
take	O
notes	O
,	O
draw	O
,	O
or	O
create	O
digital	B-Device
art	O
on	O
their	O
device	O
.	O
</s>
<s>
A	O
good	O
stylus	B-Device
can	O
make	O
a	O
huge	O
difference	O
in	O
the	O
precision	O
and	O
ease	O
of	O
use	O
when	O
interacting	O
with	O
a	O
smartphone	B-Application
,	O
especially	O
for	O
those	O
who	O
find	O
it	O
difficult	O
to	O
navigate	O
the	O
small	O
touchscreen	B-Device
with	O
their	O
fingers	O
.	O
</s>
