Balance of trade
The balance of trade is that part of a nation's balance of payments dealing with imports and exports—that is, trade in goods and services—over a given period. If exports of goods exceed imports, the trade balance is said to be "favorable"; if imports exceed exports, the trade balance is said to be "unfavorable."
A trade deficit is an amount by which a country's merchandise exports exceed its merchandise imports. It does not include "hidden exports" such as financial deals. A trade surplus is an amount by which a country's merchandise exports exceed its imports.
USA trade deficit
After a period of 70 years of being a creditor nation, the USA has became a debtor nation in 1985. Some reputable economists of the 2010's disagree on whether the USA trade deficit is a debt that ever has to be paid off.