International trade can be defined as the exchange of goods and services between countries.
What is important to note here is that international trade includes the exchange of both goods and services. People often think only of goods when they think of internatonal trade. But it is also international trade if a company in Japan hires an American lawyer or an American consultant to do work for them.
You should also note that the exchange does not need to happen between governments. If I, as an individual, buy a book from Amazon's website in Japan, that is international trade as well. So trade can be conducted by governments, businesses, organizations, or even individuals.
International trade which is also known as external trade is the exchange of goods and services between countries.
This would also help to reach a wider market, take greater advantages of economies of scale, sorce products to wider area, earn higher profits, provide additional challenges ect.