Map scale is the ratio of the length of an object or feature on a map to the true
length of the object or feature. Map scales are given in three ways: (1) by ratio or
representative fraction, such as 1:2000 or 1/2000; (2) by an equivalence, for example,
and (3) by graphically using either a bar scale or labeled grid
lines spaced throughout the map at uniform distances apart. Graphic scales permit
accurate measurements to be made on maps, even though the paper upon
which the map is printed may change dimensions.