A value-added tax (VAT) is a consumption tax placed on a product whenever value is added at each stage of the supply chain, from production to the point of sale. The amount of VAT that the user pays is on the cost of the product, less any of the costs of materials used in the product that have already been taxed.
More than 160 countries around the world use value-added taxation, and it is most commonly found in the European Union. But it is not without controversy. Advocates say it raises government revenues without punishing success or wealth, as income taxes do, and it is simpler and more standardized than a traditional sales tax, with fewer compliance issues. Critics charge that a VAT is essentially a regressive tax that places an increased economic strain on lower-income taxpayers, and also adds bureaucratic burdens for businesses.
Discount is a price reduction offered on the marked price.
Discount= Marked price-Sale price.
Sales tax is charged by the government on the selling price of an item and is included in the bill amount.
Overhead charges are the expenses incurred after buying goods.
Overhead charges have to be added to the cost price.