Foreign trade, also known as "foreign trade" or "import and export trade", refers to the exchange of goods and services between one country (region) and another country (region). This trade consists of import and export. For countries (regions) transporting goods or services, it is import; For countries (regions) that transport goods or services, it is export. This began to emerge and develop in slave society and feudal society, and developed more rapidly in capitalist society. Its nature and function are determined by different social systems.