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.
Eco-Tariffs
An Eco-tariff, also known as an environmental tariff, is a trade barrier erected for the purpose of reducing pollution and improving the environment. These trade barriers may take the form of import or export taxes on products that have a large carbon footprint or are imported from countries with lax environmental regulations.