This document discusses the costs of taxation in terms of deadweight loss. It explains that taxes reduce overall welfare by creating a wedge between the price paid by buyers and received by sellers. This leads to a reduction in quantity traded below the efficient market level. The deadweight loss is the loss of overall surplus, and grows as the tax increases and distorts market incentives more. Tax revenue initially rises with the tax rate but eventually falls as the tax starts to significantly reduce the size of the market. The deadweight loss from taxation depends on the price elasticities of supply and demand.