The document discusses customs duty in India. It defines customs duty and explains that duties are levied on imported and exported goods. The levy and rates are governed by the Customs Act of 1962 and Customs Tariff Act of 1975. Customs duty is intended to raise government revenue and protect domestic industries. Under GST, IGST is charged on imported goods based on value slabs. The document outlines various cases for determining the timing of duty based on if goods are cleared for home consumption or warehousing. It also discusses export duty timing and valuation methods for customs including transaction value, identical/similar goods, deductive value, computed value, and residual method.