In microeconomic theory a preference map or indifference map is
the collection of indifference curves possessed by an
individual. Similar in nature to a topographical map, the
contour lines of such a map demonstrating progressively more
desirable options as they move upward or to the right. Because
of the nature of indifference curves they cannot intersect and
are effectively infinite in number, their sum defining all
possible combinations of values. An individual will choose to
consume goods at the point where their budget constraint is
tangent to an indifference curve their preference map. Because
of the nature of the preference map, there is only one possible
curve and one possible consumption point on any given
combination of preference map and budget constraint. It is by
accumulating these consumption points that a demand curve can be
generated.