<s>
In	O
cartography	O
,	O
map	B-Application
coloring	I-Application
is	O
the	O
act	O
of	O
choosing	O
colors	O
as	O
a	O
form	O
of	O
map	O
symbol	O
to	O
be	O
used	O
on	O
a	O
map	O
.	O
</s>
<s>
In	O
mathematics	O
,	O
map	B-Application
coloring	I-Application
is	O
the	O
act	O
of	O
assigning	O
colors	O
to	O
features	O
of	O
a	O
map	O
such	O
that	O
no	O
two	O
adjacent	O
features	O
have	O
the	O
same	O
color	O
using	O
the	O
minimum	O
number	O
of	O
colors	O
.	O
</s>
<s>
Most	O
GIS	B-Application
programs	O
provide	O
users	O
with	O
carefully	O
curated	O
color	O
schemes	O
to	O
choose	O
from	O
,	O
thus	O
making	O
the	O
process	O
of	O
selecting	O
colors	O
easier	O
.	O
</s>
<s>
Colors	O
can	O
also	O
be	O
used	O
to	O
produce	O
three-dimensional	O
effects	O
from	O
two-dimensional	O
maps	O
,	O
either	O
by	O
explicit	B-Algorithm
color-coding	I-Algorithm
of	I-Algorithm
the	I-Algorithm
two	I-Algorithm
images	I-Algorithm
intended	O
for	O
different	O
eyes	O
,	O
or	O
by	O
using	O
the	O
characteristics	O
of	O
the	O
human	O
visual	O
system	O
to	O
make	O
the	O
map	O
look	O
three-dimensional	O
.	O
</s>
<s>
In	O
mathematics	O
there	O
is	O
a	O
close	O
link	O
between	O
map	B-Application
coloring	I-Application
and	O
graph	O
coloring	O
,	O
since	O
every	O
map	O
showing	O
different	O
areas	O
has	O
a	O
corresponding	O
graph	O
.	O
</s>
