Tariff
A tariff is a tax on imports or exports between sovereign states. It is a form of regulation of foreign trade. It is a policy that taxes foreign products to encourage or protect domestic industry. It helps limit trade deficits. The tariff is historically used to protect infant industries and to allow import substitution industrialization.
Schedules of concessions
Schedules of concessions are documents in which the specific commitments are listed. World Trade Organization (WTO) negotiations produce general rules that apply to all members, and specific commitments made by individual member governments. For trade in goods in general, these consist of maximum tariff levels. For agriculture they also include tariff quotas, limits on export subsidies, and some kinds of domestic support. The goods schedules are annexed to the General Agreement on Tariffs and Trade (GATT) and are “bound” (GATT Article II).