International economics is concerned with the effects upon economic activity of international differences in productive resources and consumer preferences and the institutions that affect them. It seeks to explain the patterns and consequences of transactions and interactions between the inhabitants of different countries, including trade, investment and migration.economies of scale are benefits from bulk buying

exchange rate: Price for which the currency of a country can be exchanged for another country's currency. Factors that influence exchange rate include.

reason of trade: transaction involving the sale and purchase of a good, service, or information.

comparative advantage: Concept in economics that a country should specialize in producing and exporting only those goods and services which it can produce more efficiently

Balance of Payments: An accounting record of all transactions made by a country over a certain time period, comparing the amount of foreign currency taken in to the amount of domestic currency paid out.