International business is composed of all commercial transactions that take place between two or more regions, countries and nations beyond their political boundaries. Typically, private companies undertake such transactions for profit; governments undertake them for profit and for political reasons. International business essentially refers to all of those business activities that involve a cross-border transaction of goods, services, and/or resources between two or more nations. Transactions of economic resources involve people, capital, and skills for interntional production of physical goods as well as services, such as finance, banking, and insurance.
This video below will define what defines a business as international. It also does a great job of differentiating an international business from a domestic business.