A Giffen good is a product that is bought by low income workers, and that defies law of demand in economics.
According to the law of demand, usually when the price of a normal good rises, its demand falls and when its price falls, the demand rises. This is different in case of giffen goods.
When price of a giffen good rises, its demand also rises and when the price of a giffen good falls, its demand also falls.
Contrary to the downward sloping demand curve of normal goods, Giffen goods have an upward sloping demand curve. Giffen goods act as a contradiction for the law of demand.
Giffen goods usually don’t have any close and proper substitutes at same price levels. But wheat and Bajra can act as an amazing example for a normal good and a giffen good respectively.
Law of demand has 5 variables, supply, demand, price, income, and substitution.
Income effect is the reason for this condition of giffen goods. Since Giffen goods fall under essential goods, consumers are willing to pay a higher price for them but this also limits disposable income which makes buying normal goods even more difficult for conumers.
Therefore, consumers end up buying even more of the Giffen goods.