Demand – The demand for a commodity refers to the quantity of a commodity, which a consumer is willing to purchase products at a given cost in a given period of time.

Law of Demand – The law of demand explains the relationships between price and the quantity demanded. Thus, other things being equal, if the price of a commodity falls, the quantity demanded of it, will rise and if the price of a commodity rises, it’s quantity demanded will decline. Thus, there is an inverse relationship between price and quantity demanded, other things being same

Exceptions to the law of demand – There are some situations where people do not increase or decrease their demands as envisaged in the law of demand –

1. Inferior goods – When the prices of giffin or inferior goods such as jowar and bajra fall, their demand also goes down because with the fall of the prices of giffin goods, the real income of households increases and they tend to substitute giffin goods by superior goods such as wheat because the consumer diverting their extra purchasing power causes by reducing in cost of giffin goods to purchase superior goods, it results falling of demand of such goods.
2. Conspicuous necessities – A commodity may be a necessity for one household and may be luxury for another. For example, washing machine, air conditioner, and microwave oven have become necessities for middle class as they convey a level of standard living but it may be luxury to lower classes so their demand is increasing even though their prices are also increasing.
3. Status symbol – Some goods are purchased not because of their intrinsic value due to their status value. For example – demand for color L.C.D. T.V., air conditioner, cat, washing machine, and many more due to their status symbol and their prices also increases.
4. Future expectations – Expectations of increasing prices in the future due to taxes, low production, and many more, which may increase the present demand of the commodities. When individuals fear that their income may fall or decreases, and unemployment may also occur in the future so they are unable to purchase products, causes reduces in the demand.
5. Change in the fashion and tastes –  When the fashion changes, demand of old fashioned commodity drops and when thete are changes in tastes in favoring of a commodity, demand will increases even if it’s price increases.