Balance of payments is a systematic record or summary statement of accounts of all the major economic or trading transactions between a reporting country and the rest of the world, during a specific period, usually one year. Balance of payment is a summary of receipts (income) and payments (expenditure) of a country in the international accounts.

Perfect Competition may be defined as many small firms manufactures and supplies the same goods (or perfect substitute) to the end-user while Monopolistic Competition is type of market where there are a handful of sellers offer a particular product leading to minimal competition, however, variants and quality of products offered by each seller are slightly different.