Paper money

Paper money, often referred to as a note or a bill (North American English), is a type of negotiable promissory note that is payable to the bearer on demand, making it a form of currency. The main types of paper money are government notes, which are directly issued by political authorities, and banknotes issued by banks,^[1] namely banks of issue including central banks. In some cases, paper money may be issued by other entities than governments or banks, for example merchants in pre-modern China and Japan.^{[citation needed]} "Banknote" is often used synonymously for paper money, not least by collectors, but in a narrow sense banknotes are only the subset of paper money that is issued by banks.^[2]

Paper money is often, but not always, legal tender, meaning that courts of law are required to recognize them as satisfactory payment of money debts.^[3]

Counterfeiting, including the forgery of paper money, is an inherent challenge. It is countered by anticounterfeiting measures in the printing of paper money. Fighting the counterfeiting of notes (and, for banks of cheques) has been a principal driver of security printing methods development in recent centuries.