Trade usually involves bargaining. Each side wants to make the best deal it can for its success.
Both sides agree on a price that satisfies and benefits both. According to David Ricardo, the country that has the lower opportunity cost in making a specific good has a comparative advantage in making that good. Comparative advantage is the ability of one country to make a good at a lower opportunity cost than that of another country. It is the nations with the comparative advantage, not necessarily the absolute advantage, that should specialize in providing and making that good. Trade impact employment, encouraging specialization and production of specific goods and services.