التعبير البياني باستخدام اللون كمتغير بصري(خارطة الكثافة السكانية في ناحية بعشيقة)

(25) .Color is regarded one of the most important visual variable ,used in mapping expression .color has three characteristics : Hue ,sturration and value .Whom researchers said that hue and saturation are used to differentiate features where as hue is used to hierarchal classes .They further asserted that color is used basically to differentiate and to arrange to ascertain degree .When achieving experimental map design regarding hue and saturation and value and carrying that test on a sample of (25) students of third grade of geography department at college of Basic Education .the result showed that changing hue showed high result regarding herarcal classes ,the second was value thus .the results showed that color can be used to classify and differentiate.