Perfect competition is  a market structure where there is a very large number of small firms, producing homogenous products. There are low barriers to entry. As a result firms cannot influence price and are price takers.

Potential growth is an increase in the potential output of an economy through an increase in the quantity/quality of resources

Price discrimination takes place when a producer charges a different price to different consumers for an identical good or service

Price elasticity of demand (PED) is a measure of the responsiveness of the quantity demanded of a good or service to a change in its price

Price elasticity of supply (PES) is a measure of the responsiveness of the quantity supplied of a good or service to a change in its price

Producer surplus is the difference between the price that producers in the market are prepared to sell their goods or service and how much they actually receive.

Progressive tax is where the higher the level of income, the higher the percentage of taxation that is paid (or the higher the average rate of taxation)