What is the diffirent between quantity demanded and demand ?

Good old Econ. :)

I think the simplest way to explain it is that demand is the relationship between the price that is charged and the amount that will be bought at that price. It is not a single quantity, but a table or graph showing a variety of prices and the corresponding amounts that consumers will buy.

Quantity demanded is the amount that will be bought at a particular price.

Thanks :D