<s>
A	O
pointing	B-Device
device	I-Device
is	O
a	O
human	B-General_Concept
interface	I-General_Concept
device	I-General_Concept
that	O
allows	O
a	O
user	O
to	O
input	O
spatial	O
(	O
i.e.	O
,	O
continuous	O
and	O
multi-dimensional	O
)	O
data	O
to	O
a	O
computer	O
.	O
</s>
<s>
CAD	B-Application
systems	O
and	O
graphical	B-Application
user	I-Application
interfaces	I-Application
(	O
GUI	B-Application
)	O
allow	O
the	O
user	O
to	O
control	O
and	O
provide	O
data	O
to	O
the	O
computer	O
using	O
physical	O
gestures	O
by	O
moving	O
a	O
hand-held	B-Application
mouse	B-Device
or	O
similar	O
device	O
across	O
the	O
surface	O
of	O
the	O
physical	O
desktop	O
and	O
activating	O
switches	O
on	O
the	O
mouse	B-Device
.	O
</s>
<s>
Movements	O
of	O
the	O
pointing	B-Device
device	I-Device
are	O
echoed	O
on	O
the	O
screen	O
by	O
movements	O
of	O
the	O
pointer	O
(	O
or	O
cursor	B-Application
)	O
and	O
other	O
visual	O
changes	O
.	O
</s>
<s>
While	O
the	O
most	O
common	O
pointing	B-Device
device	I-Device
by	O
far	O
is	O
the	O
mouse	B-Device
,	O
many	O
more	O
devices	O
have	O
been	O
developed	O
.	O
</s>
<s>
However	O
,	O
the	O
term	O
mouse	B-Device
is	O
commonly	O
used	O
as	O
a	O
metaphor	O
for	O
devices	O
that	O
move	O
a	O
computer	O
cursor	B-Application
.	O
</s>
<s>
Fitts	B-General_Concept
's	I-General_Concept
law	I-General_Concept
can	O
be	O
used	O
to	O
predict	O
the	O
speed	O
with	O
which	O
users	O
can	O
use	O
a	O
pointing	B-Device
device	I-Device
.	O
</s>
<s>
To	O
classify	O
several	O
pointing	B-Device
devices	I-Device
,	O
a	O
certain	O
number	O
of	O
features	O
can	O
be	O
considered	O
.	O
</s>
<s>
In	O
case	O
of	O
a	O
direct-input	O
pointing	B-Device
device	I-Device
,	O
the	O
on-screen	O
pointer	O
is	O
at	O
the	O
same	O
physical	O
position	O
as	O
the	O
pointing	B-Device
device	I-Device
(	O
e.g.	O
,	O
finger	O
on	O
a	O
touch	B-Device
screen	I-Device
,	O
stylus	B-Operating_System
on	O
a	O
tablet	B-Device
computer	I-Device
)	O
.	O
</s>
<s>
An	O
indirect-input	O
pointing	B-Device
device	I-Device
is	O
not	O
at	O
the	O
same	O
physical	O
position	O
as	O
the	O
pointer	O
but	O
translates	O
its	O
movement	O
onto	O
the	O
screen	O
(	O
e.g.	O
,	O
computer	B-Device
mouse	I-Device
,	O
joystick	O
,	O
stylus	B-Operating_System
on	O
a	O
graphics	B-Device
tablet	I-Device
)	O
.	O
</s>
<s>
An	O
absolute-movement	O
input	B-Device
device	I-Device
(	O
e.g.	O
,	O
stylus	B-Operating_System
,	O
finger	O
on	O
touch	B-Device
screen	I-Device
)	O
provides	O
a	O
consistent	O
mapping	O
between	O
a	O
point	O
in	O
the	O
input	O
space	O
(	O
location/state	O
of	O
the	O
input	B-Device
device	I-Device
)	O
and	O
a	O
point	O
in	O
the	O
output	O
space	O
(	O
position	O
of	O
pointer	O
on	O
screen	O
)	O
.	O
</s>
<s>
A	O
relative-movement	O
input	B-Device
device	I-Device
(	O
e.g.	O
,	O
mouse	B-Device
,	O
joystick	O
)	O
maps	O
displacement	O
in	O
the	O
input	O
space	O
to	O
displacement	O
in	O
the	O
output	O
state	O
.	O
</s>
<s>
It	O
therefore	O
controls	O
the	O
relative	O
position	O
of	O
the	O
cursor	B-Application
compared	O
to	O
its	O
initial	O
position	O
.	O
</s>
<s>
An	O
isotonic	O
pointing	B-Device
device	I-Device
is	O
movable	O
and	O
measures	O
its	O
displacement	O
(	O
mouse	B-Device
,	O
pen	O
,	O
human	O
arm	O
)	O
whereas	O
an	O
isometric	O
device	O
is	O
fixed	O
and	O
measures	O
the	O
force	O
which	O
acts	O
on	O
it	O
(	O
trackpoint	B-Device
,	O
force-sensing	O
touch	B-Device
screen	I-Device
)	O
.	O
</s>
<s>
A	O
position-control	O
input	B-Device
device	I-Device
(	O
e.g.	O
,	O
mouse	B-Device
,	O
finger	O
on	O
touch	B-Device
screen	I-Device
)	O
directly	O
changes	O
the	O
absolute	O
or	O
relative	O
position	O
of	O
the	O
on-screen	O
pointer	O
.	O
</s>
<s>
A	O
rate-control	O
input	B-Device
device	I-Device
(	O
e.g.	O
,	O
trackpoint	B-Device
,	O
joystick	O
)	O
changes	O
the	O
speed	O
and	O
direction	O
of	O
the	O
movement	O
of	O
the	O
on-screen	O
pointer	O
.	O
</s>
<s>
Different	O
pointing	B-Device
devices	I-Device
have	O
different	O
degrees	O
of	O
freedom	O
(	O
DOF	O
)	O
.	O
</s>
<s>
A	O
computer	B-Device
mouse	I-Device
has	O
two	O
degrees	O
of	O
freedom	O
,	O
namely	O
its	O
movement	O
on	O
the	O
x	B-Operating_System
-	O
and	O
y-axis	O
.	O
</s>
<s>
However	O
the	O
Wiimote	B-Device
has	O
6	O
degrees	O
of	O
freedom	O
:	O
x-	O
,	O
y	O
-	O
and	O
z-axis	O
for	O
movement	O
as	O
well	O
as	O
for	O
rotation	O
.	O
</s>
<s>
As	O
mentioned	O
later	O
in	O
this	O
article	O
,	O
pointing	B-Device
devices	I-Device
have	O
different	O
possible	O
states	O
.	O
</s>
<s>
a	O
computer	B-Device
mouse	I-Device
is	O
an	O
indirect	O
,	O
relative	O
,	O
isotonic	O
,	O
position-control	O
,	O
translational	O
input	B-Device
device	I-Device
with	O
two	O
degrees	O
of	O
freedom	O
(	O
x	B-Operating_System
,	O
y	O
position	O
)	O
and	O
two	O
states	O
(	O
tracking	O
,	O
dragging	O
)	O
.	O
</s>
<s>
a	O
touch	B-Device
screen	I-Device
is	O
a	O
direct	O
,	O
absolute	O
,	O
isometric	O
,	O
position-control	O
input	B-Device
device	I-Device
with	O
two	O
or	O
more	O
degrees	O
of	O
freedom	O
(	O
x	B-Operating_System
,	O
y	O
position	O
and	O
optionally	O
pressure	O
)	O
and	O
two	O
states	O
(	O
out	O
of	O
range	O
,	O
dragging	O
)	O
.	O
</s>
<s>
a	O
joystick	O
is	O
an	O
indirect	O
,	O
relative	O
,	O
elastic	O
,	O
rate-control	O
,	O
translational	O
input	B-Device
device	I-Device
with	O
two	O
degrees	O
of	O
freedom	O
(	O
x	B-Operating_System
,	O
y	O
angle	O
)	O
and	O
two	O
states	O
(	O
tracked	O
,	O
dragging	O
)	O
.	O
</s>
<s>
a	O
Wiimote	B-Device
is	O
an	O
indirect	O
,	O
relative	O
,	O
elastic	O
,	O
rate-control	O
,	O
translational	O
input	B-Device
device	I-Device
with	O
six	O
degrees	O
of	O
freedom	O
(	O
x	B-Operating_System
,	O
y	O
,	O
z	O
orientation	O
and	O
x	B-Operating_System
,	O
y	O
,	O
z	O
position	O
)	O
and	O
two	O
or	O
three	O
states	O
(	O
tracking	O
,	O
dragging	O
for	O
orientation	O
and	O
position	O
;	O
out-of-range	O
for	O
position	O
)	O
.	O
</s>
<s>
The	O
following	O
table	O
shows	O
a	O
classification	O
of	O
pointing	B-Device
devices	I-Device
by	O
their	O
number	O
of	O
dimensions	O
(	O
columns	O
)	O
and	O
which	O
property	O
is	O
sensed	O
(	O
rows	O
)	O
introduced	O
by	O
Bill	O
Buxton	O
.	O
</s>
<s>
stylus	B-Operating_System
)	O
(	O
M	O
)	O
and	O
touch-sensitive	B-Device
(	O
T	O
)	O
.	O
</s>
<s>
Continuous	O
manual	O
input	B-Device
devices	I-Device
are	O
categorized	O
.	O
</s>
<s>
This	O
model	O
describes	O
different	O
states	O
that	O
a	O
pointing	B-Device
device	I-Device
can	O
assume	O
.	O
</s>
<s>
Not	O
every	O
pointing	B-Device
device	I-Device
can	O
switch	O
to	O
all	O
states	O
.	O
</s>
<s>
A	O
mouse	B-Device
is	O
moved	O
without	O
the	O
button	O
being	O
pushed	O
.	O
</s>
<s>
This	O
state	O
can	O
be	O
called	O
tracking	O
,	O
meaning	O
the	O
user	O
just	O
moves	O
the	O
mouse	B-Device
without	O
further	O
interacting	O
with	O
the	O
system	O
.	O
</s>
<s>
If	O
the	O
mouse	B-Device
is	O
pointed	O
at	O
an	O
icon	O
and	O
the	O
button	O
is	O
pressed	O
while	O
moving	O
the	O
mouse	B-Device
,	O
a	O
new	O
state	O
called	O
dragging	O
is	O
entered	O
.	O
</s>
<s>
If	O
a	O
touch	O
tablet	B-Device
,	O
which	O
is	O
able	O
to	O
sense	O
touch	O
or	O
no-touch	O
,	O
is	O
used	O
instead	O
of	O
a	O
mouse	B-Device
,	O
the	O
state	O
model	O
looks	O
different	O
.	O
</s>
<s>
Only	O
when	O
the	O
finger	B-Device
touches	I-Device
the	O
display	O
,	O
the	O
state	O
switches	O
to	O
tracking	O
(	O
Figure	O
:	O
"	O
Out	O
of	O
Range	O
&	O
Tracking	O
"	O
)	O
.	O
</s>
<s>
If	O
a	O
graphics	B-Device
tablet	I-Device
with	O
a	O
stylus	B-Operating_System
is	O
used	O
,	O
it	O
is	O
possible	O
to	O
sense	O
all	O
three	O
states	O
.	O
</s>
<s>
When	O
the	O
stylus	B-Operating_System
is	O
lifted	O
,	O
it	O
is	O
out	O
of	O
range	O
.	O
</s>
<s>
When	O
it	O
is	O
in	O
range	O
,	O
the	O
state	O
switches	O
to	O
tracking	O
and	O
the	O
pointer	O
follows	O
the	O
stylus	B-Operating_System
 '	O
movement	O
.	O
</s>
<s>
Performing	O
extra	O
pressure	O
on	O
the	O
stylus	B-Operating_System
initiates	O
state	O
2	O
dragging	O
(	O
Figure	O
:	O
"	O
Out	O
of	O
Range	O
,	O
Tracking	O
&	O
Dragging	O
"	O
)	O
.	O
</s>
<s>
By	O
using	O
a	O
multiple-button	O
mouse	B-Device
or	O
multiple	O
clicks	O
,	O
State	O
2	O
can	O
be	O
split	O
into	O
a	O
set	O
of	O
states	O
,	O
i.e.	O
</s>
<s>
Fitts	B-General_Concept
's	I-General_Concept
law	I-General_Concept
(	O
often	O
cited	O
as	O
Fitts	B-General_Concept
 '	I-General_Concept
law	I-General_Concept
)	O
is	O
a	O
predictive	O
model	O
of	O
human	O
movement	O
primarily	O
used	O
in	O
human	O
–	O
computer	O
interaction	O
and	O
ergonomics	O
.	O
</s>
<s>
Fitts	B-General_Concept
's	I-General_Concept
law	I-General_Concept
is	O
used	O
to	O
model	O
the	O
act	O
of	O
pointing	O
,	O
either	O
by	O
physically	O
touching	O
an	O
object	O
with	O
a	O
hand	O
or	O
finger	O
,	O
or	O
virtually	O
,	O
by	O
pointing	O
to	O
an	O
object	O
on	O
a	O
computer	B-Device
monitor	I-Device
using	O
a	O
pointing	B-Device
device	I-Device
.	O
</s>
<s>
In	O
other	O
words	O
,	O
this	O
means	O
for	O
example	O
,	O
that	O
the	O
user	O
needs	O
more	O
time	O
to	O
click	O
on	O
a	O
small	O
button	O
which	O
is	O
distant	O
to	O
the	O
cursor	B-Application
,	O
than	O
he	O
needs	O
to	O
click	O
a	O
large	O
button	O
near	O
the	O
cursor	B-Application
.	O
</s>
<s>
a	O
and	O
b	O
are	O
constants	O
that	O
depend	O
on	O
the	O
choice	O
of	O
input	B-Device
device	I-Device
and	O
are	O
usually	O
determined	O
empirically	O
by	O
regression	O
analysis	O
.	O
</s>
<s>
Therefore	O
,	O
it	O
is	O
important	O
,	O
that	O
Fitts	B-General_Concept
 '	I-General_Concept
Law	I-General_Concept
is	O
considered	O
while	O
designing	O
user	O
interfaces	O
.	O
</s>
<s>
Larger	O
interactive	O
objects	O
are	O
easier	O
to	O
select	O
with	O
any	O
pointing	B-Device
device	I-Device
.	O
</s>
<s>
Due	O
to	O
the	O
fact	O
,	O
that	O
the	O
cursor	B-Application
gets	O
pinned	O
on	O
the	O
edges	O
and	O
corners	O
of	O
a	O
graphical	B-Application
user	I-Application
interface	I-Application
,	O
those	O
points	O
can	O
be	O
accessed	O
faster	O
than	O
other	O
spots	O
on	O
the	O
display	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
hardware	O
mouse	B-Device
moves	O
in	O
another	O
speed	O
or	O
distance	O
than	O
the	O
cursor	B-Application
on	O
the	O
screen	O
.	O
</s>
<s>
meters	O
instead	O
of	O
pixels	B-Algorithm
)	O
.	O
</s>
<s>
The	O
Microsoft	B-Application
,	O
macOS	B-Operating_System
and	O
X	B-Operating_System
window	O
systems	O
have	O
implemented	O
mechanisms	O
which	O
adapt	O
the	O
CD	O
gain	O
to	O
the	O
user	O
's	O
needs	O
.	O
</s>
<s>
the	O
CD	O
gain	O
increases	O
when	O
the	O
user	O
's	O
movement	O
velocity	O
increases	O
(	O
historically	O
referred	O
to	O
as	O
"	O
mouse	B-Device
acceleration	O
"	O
)	O
.	O
</s>
<s>
A	O
mouse	B-Device
is	O
a	O
small	O
handheld	B-Application
device	I-Application
pushed	O
over	O
a	O
horizontal	O
surface	O
.	O
</s>
<s>
A	O
mouse	B-Device
moves	O
the	O
graphical	O
pointer	O
by	O
being	O
slid	O
across	O
a	O
smooth	O
surface	O
.	O
</s>
<s>
The	O
conventional	O
roller-ball	O
mouse	B-Device
uses	O
a	O
ball	O
to	O
create	O
this	O
action	O
:	O
the	O
ball	O
is	O
in	O
contact	O
with	O
two	O
small	O
shafts	O
that	O
are	O
set	O
at	O
right	O
angles	O
to	O
each	O
other	O
.	O
</s>
<s>
As	O
the	O
ball	O
moves	O
these	O
shafts	O
rotate	O
,	O
and	O
the	O
rotation	O
is	O
measured	O
by	O
sensors	O
within	O
the	O
mouse	B-Device
.	O
</s>
<s>
The	O
distance	O
and	O
direction	O
information	O
from	O
the	O
sensors	O
is	O
then	O
transmitted	O
to	O
the	O
computer	O
,	O
and	O
the	O
computer	O
moves	O
the	O
graphical	O
pointer	O
on	O
the	O
screen	O
by	O
following	O
the	O
movements	O
of	O
the	O
mouse	B-Device
.	O
</s>
<s>
Another	O
common	O
mouse	B-Device
is	O
the	O
optical	O
mouse	B-Device
.	O
</s>
<s>
This	O
device	O
is	O
very	O
similar	O
to	O
the	O
conventional	O
mouse	B-Device
but	O
uses	O
visible	O
or	O
infrared	O
light	O
instead	O
of	O
a	O
roller-ball	O
to	O
detect	O
the	O
changes	O
in	O
position	O
.	O
</s>
<s>
Additionally	O
there	O
is	O
the	O
mini-mouse	O
,	O
which	O
is	O
a	O
small	O
egg-sized	O
mouse	B-Device
for	O
use	O
with	O
laptop	B-Device
computers	I-Device
;	O
usually	O
small	O
enough	O
for	O
use	O
on	O
a	O
free	O
area	O
of	O
the	O
laptop	B-Device
body	O
itself	O
,	O
it	O
is	O
typically	O
optical	O
,	O
includes	O
a	O
retractable	O
cord	O
and	O
uses	O
a	O
USB	B-Protocol
port	O
to	O
save	O
battery	O
life	O
.	O
</s>
<s>
A	O
trackball	B-Device
is	O
a	O
pointing	B-Device
device	I-Device
consisting	O
of	O
a	O
ball	O
housed	O
in	O
a	O
socket	O
containing	O
sensors	O
to	O
detect	O
rotation	O
of	O
the	O
ball	O
about	O
two	O
axis	O
,	O
similar	O
to	O
an	O
upside-down	O
mouse	B-Device
:	O
as	O
the	O
user	O
rolls	O
the	O
ball	O
with	O
a	O
thumb	O
,	O
fingers	O
,	O
or	O
palm	O
the	O
pointer	O
on	O
the	O
screen	O
will	O
also	O
move	O
.	O
</s>
<s>
Tracker	O
balls	O
are	O
commonly	O
used	O
on	O
CAD	B-Application
workstations	I-Application
for	O
ease	O
of	O
use	O
,	O
where	O
there	O
may	O
be	O
no	O
desk	O
space	O
on	O
which	O
to	O
use	O
a	O
mouse	B-Device
.	O
</s>
<s>
Some	O
are	O
able	O
to	O
clip	O
onto	O
the	O
side	O
of	O
the	O
keyboard	O
and	O
have	O
buttons	O
with	O
the	O
same	O
functionality	O
as	O
mouse	B-Device
buttons	O
.	O
</s>
<s>
There	O
are	O
also	O
wireless	O
trackballs	B-Device
which	O
offer	O
a	O
wider	O
range	O
of	O
ergonomic	O
positions	O
to	O
the	O
user	O
.	O
</s>
<s>
Isometric	B-Device
joysticks	I-Device
are	O
where	O
the	O
user	O
controls	O
the	O
stick	O
by	O
varying	O
the	O
amount	O
of	O
force	O
they	O
push	O
with	O
,	O
and	O
the	O
position	O
of	O
the	O
stick	O
remains	O
more	O
or	O
less	O
constant	O
.	O
</s>
<s>
Isometric	B-Device
joysticks	I-Device
are	O
often	O
cited	O
as	O
more	O
difficult	O
to	O
use	O
due	O
to	O
the	O
lack	O
of	O
tactile	O
feedback	O
provided	O
by	O
an	O
actual	O
moving	O
joystick	O
.	O
</s>
<s>
A	O
pointing	B-Device
stick	I-Device
is	O
a	O
pressure-sensitive	O
small	O
nub	O
used	O
like	O
a	O
joystick	O
.	O
</s>
<s>
It	O
is	O
usually	O
found	O
on	O
laptops	B-Device
embedded	O
between	O
the	O
G	O
,	O
H	O
,	O
and	O
B	O
keys	O
.	O
</s>
<s>
The	O
corresponding	O
"	O
mouse	B-Device
"	O
buttons	O
are	O
commonly	O
placed	O
just	O
below	O
the	O
space	B-Device
bar	I-Device
.	O
</s>
<s>
The	B-Operating_System
Wii	I-Operating_System
Remote	O
,	O
also	O
known	O
colloquially	O
as	O
the	O
Wiimote	B-Device
,	O
is	O
the	O
primary	O
controller	O
for	O
Nintendo	B-Operating_System
's	I-Operating_System
Wii	I-Operating_System
console	I-Operating_System
.	O
</s>
<s>
A	O
main	O
feature	O
of	O
the	B-Operating_System
Wii	I-Operating_System
Remote	O
is	O
its	O
motion	O
sensing	O
capability	O
,	O
which	O
allows	O
the	O
user	O
to	O
interact	O
with	O
and	O
manipulate	O
items	O
on	O
screen	O
via	O
gesture	O
recognition	O
and	O
pointing	O
through	O
the	O
use	O
of	O
accelerometer	O
and	O
optical	O
sensor	O
technology	O
.	O
</s>
<s>
A	O
finger	B-Algorithm
tracking	I-Algorithm
device	O
tracks	O
fingers	O
in	O
the	O
3D	O
space	O
or	O
close	O
to	O
the	O
surface	O
without	O
contact	O
with	O
a	O
screen	O
.	O
</s>
<s>
A	O
graphics	B-Device
tablet	I-Device
or	O
digitizing	B-Device
tablet	I-Device
is	O
a	O
special	O
tablet	B-Device
similar	O
to	O
a	O
touchpad	B-Application
,	O
but	O
controlled	O
with	O
a	O
pen	O
or	O
stylus	B-Operating_System
that	O
is	O
held	O
and	O
used	O
like	O
a	O
normal	O
pen	O
or	O
pencil	O
.	O
</s>
<s>
The	O
thumb	O
usually	O
controls	O
the	O
clicking	O
via	O
a	O
two-way	O
button	O
on	O
the	O
top	O
of	O
the	O
pen	O
,	O
or	O
by	O
tapping	O
on	O
the	O
tablet	B-Device
's	O
surface	O
.	O
</s>
<s>
A	O
cursor	B-Application
(	O
also	O
called	O
a	O
puck	O
)	O
is	O
similar	O
to	O
a	O
mouse	B-Device
,	O
except	O
that	O
it	O
has	O
a	O
window	O
with	O
cross	O
hairs	O
for	O
pinpoint	O
placement	O
,	O
and	O
it	O
can	O
have	O
as	O
many	O
as	O
16	O
buttons	O
.	O
</s>
<s>
A	O
pen	O
(	O
also	O
called	O
a	O
stylus	B-Operating_System
)	O
looks	O
like	O
a	O
simple	O
ballpoint	O
pen	O
but	O
uses	O
an	O
electronic	O
head	O
instead	O
of	O
ink	O
.	O
</s>
<s>
The	O
tablet	B-Device
contains	O
electronics	O
that	O
enable	O
it	O
to	O
detect	O
movement	O
of	O
the	O
cursor	B-Application
or	O
pen	O
and	O
translate	O
the	O
movements	O
into	O
digital	O
signals	O
that	O
it	O
sends	O
to	O
the	O
computer.	O
"	O
</s>
<s>
This	O
is	O
different	O
from	O
a	O
mouse	B-Device
because	O
each	O
point	O
on	O
the	O
tablet	B-Device
represents	O
a	O
point	O
on	O
the	O
screen	O
.	O
</s>
<s>
A	O
stylus	B-Operating_System
is	O
a	O
small	O
pen-shaped	O
instrument	O
that	O
is	O
used	O
to	O
input	O
commands	O
to	O
a	O
computer	B-Device
screen	I-Device
,	O
mobile	B-Application
device	I-Application
or	O
graphics	B-Device
tablet	I-Device
.	O
</s>
<s>
The	O
stylus	B-Operating_System
is	O
the	O
primary	O
input	B-Device
device	I-Device
for	O
personal	B-Application
digital	I-Application
assistants	I-Application
,	O
smartphones	B-Application
and	O
some	O
handheld	B-Application
gaming	I-Application
systems	I-Application
such	O
as	O
the	O
Nintendo	B-Device
DS	I-Device
that	O
require	O
accurate	O
input	O
,	O
although	O
devices	O
featuring	O
multi-touch	B-Application
finger-input	O
with	O
capacitive	O
touchscreens	B-Device
have	O
become	O
more	O
popular	O
than	O
stylus-driven	O
devices	O
in	O
the	O
smartphone	B-Application
market	O
.	O
</s>
<s>
A	O
touchpad	B-Application
or	O
trackpad	O
is	O
a	O
flat	O
surface	O
that	O
can	O
detect	O
finger	O
contact	O
.	O
</s>
<s>
It	O
is	O
a	O
stationary	O
pointing	B-Device
device	I-Device
,	O
commonly	O
used	O
on	O
laptop	B-Device
computers	I-Device
.	O
</s>
<s>
At	O
least	O
one	O
physical	O
button	O
normally	O
comes	O
with	O
the	O
touchpad	B-Application
,	O
but	O
the	O
user	O
can	O
also	O
generate	O
a	O
mouse	B-Device
click	O
by	O
tapping	O
on	O
the	O
pad	O
.	O
</s>
<s>
A	O
touchscreen	B-Device
is	O
a	O
device	O
embedded	O
into	O
the	O
screen	O
of	O
the	O
TV	O
monitor	O
,	O
or	O
system	O
LCD	B-Device
monitor	O
screens	O
of	O
laptop	B-Device
computers	I-Device
.	O
</s>
<s>
Resistive	O
and	O
capacitive	O
touchscreens	B-Device
have	O
conductive	O
materials	O
embedded	O
in	O
the	O
glass	O
and	O
detect	O
the	O
position	O
of	O
the	O
touch	O
by	O
measuring	O
changes	O
in	O
electric	O
current	O
.	O
</s>
<s>
Modern	O
touchscreens	B-Device
could	O
be	O
used	O
in	O
conjunction	O
with	O
stylus	B-Operating_System
pointing	B-Device
devices	I-Device
,	O
while	O
those	O
powered	O
by	O
infrared	O
do	O
not	O
require	O
physical	O
touch	O
,	O
but	O
just	O
recognize	O
the	O
movement	O
of	O
hand	O
and	O
fingers	O
in	O
some	O
minimum	O
range	O
distance	O
from	O
the	O
real	O
screen	O
.	O
</s>
<s>
Touchscreens	B-Device
became	O
popular	O
with	O
the	O
introduction	O
of	O
palmtop	B-Operating_System
computers	I-Operating_System
like	O
those	O
sold	O
by	O
the	O
Palm	O
,	O
Inc	O
.	O
hardware	O
manufacturer	O
,	O
some	O
high	O
range	O
classes	O
of	O
laptop	B-Device
computers	I-Device
,	O
mobile	O
smartphone	B-Application
like	O
HTC	O
or	O
the	O
Apple	O
iPhone	B-Device
,	O
and	O
the	O
availability	O
of	O
standard	O
touchscreen	B-Device
device	O
drivers	O
into	O
the	O
Symbian	B-Operating_System
,	O
Palm	B-Operating_System
OS	I-Operating_System
,	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
,	O
and	O
Microsoft	B-Application
Windows	I-Application
operating	I-Application
systems	I-Application
.	O
</s>
<s>
Typical	O
representatives	O
can	O
be	O
found	O
on	O
notebook	B-Device
's	O
keyboards	O
between	O
the	O
"	O
G	O
"	O
and	O
"	O
H	O
"	O
keys	O
.	O
</s>
<s>
By	O
performing	O
pressure	O
on	O
the	O
TrackPoint	B-Device
,	O
the	O
cursor	B-Application
moves	O
on	O
the	O
display	O
.	O
</s>
<s>
A	O
light	B-Device
pen	I-Device
is	O
a	O
device	O
similar	O
to	O
a	O
touch	B-Device
screen	I-Device
,	O
but	O
uses	O
a	O
special	O
light-sensitive	O
pen	O
instead	O
of	O
the	O
finger	O
,	O
which	O
allows	O
for	O
more	O
accurate	O
screen	O
input	O
.	O
</s>
<s>
As	O
the	O
tip	O
of	O
the	O
light	B-Device
pen	I-Device
makes	O
contact	O
with	O
the	O
screen	O
,	O
it	O
sends	O
a	O
signal	O
back	O
to	O
the	O
computer	O
containing	O
the	O
coordinates	O
of	O
the	O
pixels	B-Algorithm
at	O
that	O
point	O
.	O
</s>
<s>
It	O
can	O
be	O
used	O
to	O
draw	O
on	O
the	O
computer	B-Device
screen	I-Device
or	O
make	O
menu	O
selections	O
,	O
and	O
does	O
not	O
require	O
a	O
special	O
touch	B-Device
screen	I-Device
because	O
it	O
can	O
work	O
with	O
any	O
CRT	B-Device
display	I-Device
.	O
</s>
<s>
Puck	O
,	O
similar	O
to	O
a	O
mouse	B-Device
,	O
but	O
,	O
but	O
designed	O
for	O
absolute	O
positioning	O
rather	O
than	O
relative	O
.	O
</s>
<s>
Pucks	O
are	O
most	O
commonly	O
used	O
for	O
tracing	O
in	O
CAD/CAM/CAE	O
work	O
.	O
</s>
<s>
Gyroscopic	O
mouse	B-Device
–	O
a	O
gyroscope	B-Application
senses	O
the	O
movement	O
of	O
the	O
mouse	B-Device
as	O
it	O
moves	O
through	O
the	O
air	O
.	O
</s>
<s>
Users	O
can	O
operate	O
a	O
gyroscopic	O
mouse	B-Device
when	O
they	O
have	O
no	O
room	O
for	O
a	O
regular	O
mouse	B-Device
or	O
must	O
give	O
commands	O
while	O
standing	O
up	O
.	O
</s>
<s>
This	O
input	B-Device
device	I-Device
needs	O
no	O
cleaning	O
and	O
can	O
have	O
many	O
extra	O
buttons	O
,	O
in	O
fact	O
,	O
some	O
laptops	B-Device
doubling	O
as	O
TVs	O
come	O
with	O
gyroscopic	O
mice	O
that	O
resemble	O
,	O
and	O
double	O
as	O
,	O
remotes	O
with	O
LCD	B-Device
screens	I-Device
built	O
in	O
.	O
</s>
