Every industry has its unique terms, and international trade is no different. Words like "bailment", "mala fides", and "tender" have their own special meanings in the business of trade, and if you want to learn them, go to the Dictionary of International Trade Terms. This dictionary, part of the International Trade Data System of the U.S. Customs Service, has hundreds of definitions of trade terms, written in layman's language. You'll get an education in international trade just by browsing the entries at this site. You'll also find downloadable harmonized tariff schedules here, as well as dozens of other useful links for trade (under Importing/Exporting Resources).