IGST stands for Integrated Goods and Services Tax. It is a tax levied by the central government on the inter-state supply of goods and services in India. Interstate supply refers to the supply of goods or services from one state to another state within the country. In such cases, the IGST is levied in addition to the value of the goods or services, and the revenue collected from IGST goes to the central government. The IGST rate is determined by the central government, and it is based on the rate specified in the Integrated GST Act. The IGST system helps in ensuring the seamless flow of goods and services across the states and helps in preventing the cascading of taxes.