<s>
The	O
key	O
,	O
short	O
form	O
for	O
function	O
,	O
is	O
a	O
modifier	B-Device
key	I-Device
on	O
many	O
keyboards	B-Device
,	O
especially	O
on	O
laptops	B-Device
,	O
used	O
in	O
a	O
compact	O
layout	O
to	O
combine	O
keys	O
which	O
are	O
usually	O
kept	O
separate	O
.	O
</s>
<s>
It	O
is	O
typically	O
found	O
on	O
laptops	B-Device
due	O
to	O
their	O
keyboard	B-Device
size	O
restrictions	O
.	O
</s>
<s>
It	O
is	O
also	O
found	O
on	O
many	O
full-sized	O
"	O
multimedia	O
"	O
keyboards	B-Device
as	O
the	O
F-Lock	B-Device
key	O
.	O
</s>
<s>
Typically	O
,	O
in	O
a	O
compact	O
layout	O
the	O
main	O
area	O
of	O
the	O
keyboard	B-Device
(	O
containing	O
the	O
letter	O
keys	O
)	O
is	O
kept	O
in	O
much	O
the	O
same	O
layout	O
as	O
with	O
a	O
full-sized	O
keyboard	B-Device
,	O
and	O
the	O
numeric	B-Device
keypad	I-Device
is	O
moved	O
to	O
share	O
a	O
group	O
of	O
central	O
keys	O
.	O
</s>
<s>
This	O
allows	O
typists	B-General_Concept
to	O
enter	O
text	O
without	O
having	O
to	O
learn	O
a	O
new	O
layout	O
.	O
</s>
<s>
This	O
78-key	O
UK	O
layout	O
is	O
taken	O
from	O
the	O
Apple	B-Device
iBook	I-Device
.	O
</s>
<s>
Characters	O
in	O
blue	O
are	O
accessed	O
through	O
the	O
Fn	B-Device
key	I-Device
,	O
but	O
functions	O
on	O
the	O
top	O
row	O
can	O
be	O
accessed	O
without	O
Fn	B-Device
key	I-Device
in	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
.	O
</s>
<s>
Fn	O
is	O
a	O
modifier	B-Device
key	I-Device
,	O
and	O
works	O
like	O
other	O
modifiers	O
keys	O
,	O
such	O
as	O
Ctrl	B-Device
,	O
Shift	B-Device
,	O
Alt	B-Device
and	O
AltGr	B-Device
.	O
</s>
<s>
For	O
a	O
standard	O
modifier	B-Device
key	I-Device
,	O
the	O
microcontroller	B-Architecture
inside	O
the	O
keyboard	B-Device
sends	O
a	O
scancode	O
for	O
the	O
modifier	O
itself	O
,	O
which	O
is	O
then	O
interpreted	O
by	O
the	O
operating	B-General_Concept
system	I-General_Concept
and	O
combined	O
with	O
other	O
simultaneous	O
key-presses	O
.	O
</s>
<s>
The	O
Fn	B-Device
key	I-Device
is	O
a	O
form	O
of	O
meta-modifier	O
key	O
,	O
in	O
that	O
it	O
causes	O
the	O
operating	B-General_Concept
system	I-General_Concept
to	O
see	O
altered	O
scancodes	O
when	O
other	O
keys	O
on	O
the	O
keyboard	B-Device
are	O
pressed	O
.	O
</s>
<s>
This	O
allows	O
the	O
keyboard	B-Device
to	O
directly	O
emulate	B-Application
a	O
full-sized	O
keyboard	B-Device
,	O
so	O
the	O
operating	B-General_Concept
system	I-General_Concept
can	O
use	O
standard	O
keymaps	O
designed	O
for	O
a	O
full-sized	O
keyboard	B-Device
.	O
</s>
<s>
However	O
,	O
because	O
the	O
operating	B-General_Concept
system	I-General_Concept
has	O
no	O
notion	O
of	O
the	O
Fn	B-Device
key	I-Device
,	O
the	O
key	O
can	O
not	O
normally	O
be	O
remapped	O
in	O
software	O
,	O
unlike	O
all	O
other	O
standard	O
keyboard	B-Device
keys	O
.	O
</s>
<s>
While	O
it	O
is	O
most	O
common	O
for	O
the	O
Fn	B-Device
key	I-Device
processing	O
to	O
happen	O
directly	O
in	O
the	O
keyboard	B-Device
micro-controller	B-Architecture
,	O
offering	O
no	O
knowledge	O
to	O
the	O
main	O
computer	O
of	O
whether	O
the	O
Fn	B-Device
key	I-Device
was	O
pressed	O
,	O
some	O
manufacturers	O
,	O
like	O
Lenovo	O
,	O
perform	O
this	O
mapping	O
in	O
BIOS	B-Operating_System
running	O
on	O
the	O
main	O
CPU	O
,	O
allowing	O
remapping	O
the	O
Fn	B-Device
key	I-Device
by	O
modifying	O
the	O
BIOS	B-Operating_System
interrupt	B-General_Concept
handler	I-General_Concept
;	O
and	O
Apple	O
,	O
in	O
which	O
the	O
Fn	B-Device
key	I-Device
is	O
mappable	O
and	O
serves	O
other	O
uses	O
too	O
,	O
as	O
triggering	O
the	O
Dictation	O
function	O
by	O
pressing	O
the	O
Fn	B-Device
key	I-Device
twice	O
.	O
</s>
<s>
In	O
addition	O
to	O
being	O
mapped	O
to	O
standard	O
keyboard	B-Device
keys	O
like	O
Scroll	B-Device
Lock	I-Device
and	O
Num	B-Device
Lock	I-Device
,	O
the	O
Fn	B-Device
key	I-Device
combinations	O
may	O
also	O
be	O
mapped	O
to	O
control	O
system	O
interfaces	O
to	O
change	O
the	O
LCD	B-Device
brightness	O
,	O
VGA	B-Protocol
output	O
,	O
or	O
speaker	O
volume	O
on	O
most	O
laptop	B-Device
computers	I-Device
.	O
</s>
<s>
There	O
is	O
not	O
yet	O
an	O
agreed-upon	O
standard	O
for	O
the	O
placement	O
of	O
the	O
Fn	B-Device
key	I-Device
,	O
although	O
most	O
manufacturers	O
have	O
elected	O
to	O
place	O
it	O
alongside	O
a	O
shrunken	O
and/or	O
displaced	O
left	O
Control	B-Device
key	I-Device
.	O
</s>
<s>
Because	O
the	O
Control	B-Device
key	I-Device
is	O
most	O
frequently	O
associated	O
with	O
OS	O
and	O
application	O
shortcuts	O
(	O
such	O
as	O
Control+S	O
to	O
save	O
a	O
document	O
,	O
or	O
Control+Shift+Escape	O
to	O
launch	O
the	O
Task	O
Manager	O
in	O
modern	O
versions	O
of	O
Microsoft	B-Application
Windows	I-Application
)	O
,	O
altering	O
its	O
size	O
and	O
placement	O
is	O
often	O
regarded	O
as	O
inconvenient	O
for	O
users	O
accustomed	O
to	O
the	O
larger	O
left	O
Control	B-Device
key	I-Device
on	O
IBM	B-Device
PC-style	I-Device
keyboards	I-Device
commonly	O
used	O
for	O
desktop	O
computers	O
.	O
</s>
<s>
The	O
majority	O
of	O
portable	O
computer	O
manufacturers	O
today	O
(	O
including	O
HP	O
,	O
Dell	O
,	O
and	O
Samsung	B-Application
)	O
currently	O
place	O
the	O
Fn	B-Device
key	I-Device
between	O
the	O
left	O
Control	B-Device
key	I-Device
and	O
the	O
left	O
Windows	B-Device
key	I-Device
,	O
making	O
it	O
the	O
second	O
key	O
from	O
the	O
left	O
on	O
the	O
bottom	O
row	O
of	O
the	O
keyboard	B-Device
.	O
</s>
<s>
This	O
usually	O
means	O
that	O
the	O
Control	B-Device
key	I-Device
is	O
reduced	O
in	O
size	O
,	O
but	O
allows	O
it	O
to	O
remain	O
in	O
the	O
lowest-left	O
position	O
on	O
the	O
keyboard	B-Device
.	O
</s>
<s>
Conversely	O
,	O
Lenovo	O
currently	O
arrange	O
keyboards	B-Device
on	O
their	O
ThinkPad	B-Operating_System
computers	O
with	O
the	O
Fn	B-Device
key	I-Device
as	O
the	O
lowest-left	O
,	O
making	O
Control	O
the	O
second-from-left	O
on	O
the	O
bottom	O
row	O
.	O
</s>
<s>
This	O
arrangement	O
is	O
currently	O
unique	O
to	O
ThinkPads	B-Operating_System
amongst	O
all	O
laptops	B-Device
shipped	O
with	O
Windows	O
,	O
but	O
it	O
is	O
one	O
that	O
has	O
been	O
in	O
place	O
since	O
the	O
modern	O
ThinkPad	B-Operating_System
product	O
line	O
was	O
introduced	O
by	O
IBM	O
in	O
1992	O
.	O
</s>
<s>
IBM	O
designers	O
chose	O
this	O
arrangement	O
at	O
least	O
in	O
part	O
because	O
it	O
allowed	O
the	O
laptop	B-Device
's	O
ThinkLight	B-Device
to	O
be	O
turned	O
on	O
in	O
the	O
dark	O
simply	O
by	O
feeling	O
for	O
the	O
keys	O
in	O
two	O
of	O
the	O
keyboard	B-Device
's	O
corners	O
.	O
</s>
<s>
Notably	O
,	O
ThinkPads	B-Operating_System
did	O
not	O
include	O
Windows	B-Device
keys	I-Device
on	O
any	O
of	O
their	O
keyboards	B-Device
until	O
2006	O
,	O
which	O
meant	O
that	O
though	O
the	O
left	O
Control	B-Device
key	I-Device
was	O
displaced	O
by	O
the	O
Fn	B-Device
key	I-Device
,	O
neither	O
it	O
nor	O
the	O
left	B-Device
Alt	I-Device
key	I-Device
needed	O
to	O
be	O
made	O
smaller	O
.	O
</s>
<s>
The	O
inclusion	O
of	O
Windows	B-Device
keys	I-Device
on	O
ThinkPad	B-Operating_System
models	O
from	O
mid-2006	O
onwards	O
was	O
achieved	O
mainly	O
by	O
shrinking	O
the	O
left	B-Device
Alt	I-Device
key	I-Device
,	O
which	O
means	O
that	O
ThinkPad	B-Operating_System
keyboards	B-Device
now	O
generally	O
have	O
larger	O
left	O
Control	B-Device
keys	I-Device
than	O
those	O
of	O
many	O
other	O
manufacturers	O
,	O
and	O
are	O
unique	O
in	O
preserving	O
on	O
laptops	B-Device
the	O
Control	O
,	O
Windows	O
,	O
and	O
Alt	B-Device
key	I-Device
arrangement	O
used	O
on	O
most	O
desktop	O
keyboards	B-Device
.	O
</s>
<s>
Many	O
laptops	B-Device
place	O
the	O
Fn	B-Device
key	I-Device
at	O
a	O
less	O
convenient	O
position	O
(	O
and	O
with	O
a	O
smaller	O
size	O
)	O
within	O
the	O
top	O
row	O
of	O
functions	O
keys	O
F1	O
to	O
F12	O
and	O
other	O
"	O
multimedia	O
"	O
or	O
manufacturer-specific	O
device/power	O
control	B-Device
key	I-Device
.	O
</s>
<s>
Apple	O
also	O
place	O
the	O
Fn	B-Device
key	I-Device
at	O
the	O
bottom	O
left	O
of	O
the	O
keyboard	B-Device
,	O
displacing	O
and	O
shrinking	O
the	O
left	O
Control	B-Device
key	I-Device
,	O
though	O
this	O
is	O
less	O
controversial	O
as	O
macOS	B-Application
,	O
the	O
main	O
operating	B-General_Concept
system	I-General_Concept
for	O
most	O
Apple	O
laptops	B-Device
,	O
is	O
much	O
less	O
reliant	O
on	O
the	O
Control	B-Device
key	I-Device
for	O
shortcuts	O
and	O
modifiers	O
than	O
Windows	O
or	O
Unix-like	O
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
This	O
inconsistency	O
between	O
manufacturers	O
,	O
and	O
the	O
overall	O
issue	O
of	O
Control	B-Device
key	I-Device
shrinkage	O
,	O
has	O
long	O
been	O
a	O
point	O
of	O
contention	O
between	O
laptop	B-Device
purchasers	O
and	O
users	O
,	O
which	O
is	O
aggravated	O
by	O
the	O
fact	O
that	O
on	O
most	O
keyboards	B-Device
the	O
Fn	B-Device
key	I-Device
is	O
mapped	O
at	O
the	O
hardware	O
level	O
and	O
so	O
cannot	O
be	O
remapped	O
(	O
that	O
is	O
,	O
reconfigured	O
or	O
virtually	O
"	O
moved	O
"	O
)	O
at	O
the	O
OS	O
level	O
.	O
</s>
<s>
Lenovo	O
,	O
however	O
,	O
have	O
since	O
circa	O
2011	O
allowed	O
users	O
to	O
reverse	O
the	O
Fn	O
and	O
left	O
Control	B-Device
key	I-Device
arrangement	O
via	O
a	O
BIOS	B-Operating_System
setting	O
.	O
</s>
<s>
Other	O
manufacturers	O
have	O
chosen	O
to	O
map	O
the	O
Fn	B-Device
key	I-Device
not	O
to	O
the	O
left	O
of	O
the	O
space	O
bar	O
but	O
instead	O
to	O
the	O
right	O
,	O
so	O
that	O
the	O
space	O
bar	O
can	O
be	O
better	O
centered	O
with	O
the	O
rest	O
positions	O
(	O
alphabetic	O
keys	O
F	O
and	O
J	O
on	O
Latin	O
layouts	O
)	O
,	O
without	O
sacrificing	O
the	O
width	O
of	O
the	O
left	O
Control	O
and	O
left	B-Device
Alt	I-Device
key	I-Device
(	O
already	O
reduced	O
by	O
the	O
insertion	O
of	O
the	O
left	O
Win	O
key	O
between	O
them	O
)	O
,	O
while	O
keeping	O
AltGr	B-Device
on	O
the	O
right	O
large	O
enough	O
for	O
more	O
frequent	O
use	O
on	O
international	O
layouts	O
;	O
in	O
that	O
case	O
,	O
the	O
Fn	B-Device
key	I-Device
just	O
replaces	O
the	O
second	O
Win	O
key	O
(	O
which	O
is	O
optional	O
and	O
in	O
fact	O
not	O
needed	O
)	O
of	O
extended	O
PC	B-Device
keyboards	I-Device
.	O
</s>
<s>
Other	O
manufacturers	O
have	O
placed	O
the	O
Fn	B-Device
key	I-Device
at	O
end	O
of	O
row	O
B	O
,	O
immediately	O
to	O
the	O
right	O
of	O
the	O
second	O
Shift	B-Device
key	I-Device
which	O
is	O
larger	O
than	O
necessary	O
for	O
typing	O
text	O
,	O
in	O
order	O
to	O
map	O
the	O
second	O
Win	O
key	O
next	O
to	O
the	O
right	O
of	O
AltGr	B-Device
,	O
or	O
to	O
preserve	O
the	O
conventional	O
placement	O
of	O
Japanese	O
input	O
mode	O
keys	O
.	O
</s>
<s>
A	O
different	O
solution	O
,	O
which	O
side-steps	O
the	O
Fn	B-Device
key	I-Device
placement	O
issue	O
altogether	O
,	O
is	O
to	O
remap	O
the	O
Caps-Lock	O
key	O
as	O
Control	O
.	O
</s>
<s>
This	O
emulates	B-Application
the	O
layout	O
of	O
the	O
IBM	B-Device
Model	I-Device
F	I-Device
keyboard	I-Device
for	O
the	O
original	O
IBM	O
PC	O
,	O
which	O
placed	O
the	O
Caps-Lock	O
key	O
where	O
right	O
Control	O
is	O
found	O
on	O
modern	O
keyboards	B-Device
,	O
a	O
location	O
that	O
is	O
favoured	O
by	O
some	O
Vim	O
and	O
Emacs	O
users	O
because	O
of	O
its	O
prominent	O
location	O
and	O
long-time	O
use	O
on	O
Unix	B-Device
workstations	I-Device
.	O
</s>
<s>
Other	O
factors	O
include	O
the	O
control	B-Device
key	I-Device
's	O
size	O
,	O
displacement	O
,	O
and	O
position	O
relative	O
to	O
the	O
left-shift	O
key	O
.	O
</s>
<s>
Executing	O
a	O
control-and-shift	O
operation	O
with	O
a	O
right-displaced-control	O
involves	O
curling	O
the	O
little	O
finger	O
slightly	O
underneath	O
the	O
ring-finger	O
.	O
</s>
<s>
Control	B-Device
key	I-Device
combinations	O
involving	O
the	O
upper-left	O
of	O
the	O
keyboard	B-Device
,	O
including	O
the	O
keys	O
(	O
1	O
,	O
Q	O
,	O
W	O
,	O
2	O
)	O
require	O
either	O
moving	O
the	O
hand	O
,	O
or	O
using	O
the	O
right-control	O
key	O
with	O
the	O
opposite	O
hand	O
.	O
</s>
<s>
It	O
also	O
allows	O
control-and-shift	O
operations	O
to	O
be	O
performed	O
without	O
curling	O
the	O
little	O
finger	O
underneath	O
.	O
</s>
<s>
Some	O
workarounds	O
include	O
using	O
little-finger-shift	O
and	O
ring-finger-control	O
or	O
thumb-control	O
presses	O
.	O
</s>
<s>
Such	O
change	O
to	O
the	O
point	O
of	O
origin	O
does	O
reduce	O
the	O
useful	O
radius	O
of	O
the	O
first	O
four	O
fingers	O
across	O
the	O
keyboard	B-Device
,	O
yet	O
may	O
be	O
more	O
ergonomic	O
for	O
the	O
hand	O
.	O
</s>
<s>
On	O
a	O
fullsize	O
keyboard	B-Device
,	O
some	O
users	O
access	O
the	O
lower-left	O
Control	B-Device
key	I-Device
using	O
the	O
side	O
of	O
their	O
palm	O
,	O
a	O
technique	O
which	O
is	O
not	O
generally	O
possible	O
on	O
shallow	O
throw	O
laptop	B-Device
keyboards	B-Device
with	O
wrist	O
rests	O
.	O
</s>
<s>
Fn	B-Device
key	I-Device
features	O
vary	O
from	O
keyboard	B-Device
to	O
keyboard	B-Device
,	O
but	O
the	O
common	O
ones	O
are	O
the	O
following	O
:	O
</s>
