plz.... give the difference between demand,desire and want....

Demand, Desire and wants are three different but similar concepts. Desire refers to the wishes or the things for which a human yearns for, such as buying a car or buying an expensive watch, etc. Such wishes may not always materialise into reality due to lack of purchasing power. However, when these desires turn into reality then they become the demands for that product. This happens when the person has enough purchasing power to buy the things he desire. On a similar note, wants refer to the more specified demand. That is, wants are specified to an object which are culturally shaped within the human desires and needs, such as a Mercedes car or a Rolls-Royce watch.