Means the quantity of a good or a service that people want to buy at a range of different prices. Market demand refers to the level of demand which comes from everyone in a particular market. Effective demand means demand backed by the ability to pay for the product. Aggregate demand means demand for all goods and services available in the economy as a whole.
The level of demand for individual products may be influenced by:
• Tastes or fashions
• Changes in the prices of other goods, be they substitutes or complementary goods .
Individual demand will be particularly influenced by incomes and family circumstances.