Query: The United States dollar is not a form of currency.

Relevant passages:
United States dollar <=SEP=> Infobox currency  | currency_name_in_local =  | image_1 = USDnotes.png  | image_title_1 = Federal Reserve Notes  | iso_code = USD  | iso_number = 840  | iso_exponent = 2  | superunit_name_1 = eagle  | subunit_name_1 = dime  | symbol = $  | nickname =  | frequently_used_banknotes = $ 1 , $ 5 , $ 10 , $ 20 , $ 50 , $ 100  | rarely_used_banknotes = $ 2  | frequently_used_coins = 1 cents , 5 cents , 10 cents , 25 cents  | rarely_used_coins = 50 cents , $ 1  | superunit_ratio_1 = 10  | superunit_ratio_2 = 100  | superunit_ratio_3 = 1000  | superunit_name_2 = union  | superunit_name_3 = grand  | subunit_ratio_1 =  | subunit_ratio_2 =  | subunit_ratio_3 =  | subunit_name_2 = cent  | subunit_name_3 = mill  | symbol_subunit_2 = cents  | symbol_subunit_3 =  | banknote_article = Banknotes of the United States dollar  | coin_article = Coins of the United States dollar  | using_countries = Alongside East Timor centavo coinsAlongside Ecuadorian centavo coinsAlongside Panamanian balboa coinsOfficial currency for Zimbabwean government transactions   | unofficial_users =   The United States dollar ( sign : $ ; code : USD ; also abbreviated US$ and referred to as the dollar , U.S. dollar , or American dollar ) is the official currency of the United States and its insular territories per the United States Constitution . It is divided into 100 smaller cent units . The circulating paper money consists of Federal Reserve Notes that are denominated in United States dollars .   The U.S. dollar is commodity money of silver as enacted by the Coinage Act of 1792 which determined the dollar to be 371 4/16 grain ( 24.1 g ) pure or 416 grain ( 27.0 g ) standard silver . Since the currency is the most used in international transactions , it is the world 's primary reserve currency . Several countries use it as their official currency , and in many others it is the de facto currency . Besides the United States , it is also used as the sole currency in two British Overseas Territories in the Caribbean : the British Virgin Islands and Turks and Caicos Islands . A few countries use the Federal Reserve Notes for paper money , while still minting their own coins , or also accept U.S. dollar coins ( such as the Susan B. Anthony dollar ) .

Reserve currency <=SEP=> A reserve currency ( or anchor currency ) is a currency that is held in significant quantities by governments and institutions as part of their foreign exchange reserves . The reserve currency is commonly used in international transactions , international investments and all aspects of the global economy . It is often considered a hard currency or safe-haven currency . People who live in a country that issues a reserve currency can purchase imports and borrow across borders more cheaply than people in other nations because they do not need to exchange their currency to do so .   By the end of the 20th century , the United States dollar was considered the world 's most dominant reserve currency , followed by the Euro . The world 's need for dollars has allowed the United States government as well as Americans to borrow at lower costs , granting them an advantage in excess of $ 100 billion per year . However , the U.S. dollar 's status as a reserve currency , by increasing its value , hurts U.S. exporters .

International use of the U.S. dollar <=SEP=> Besides being the main currency of the United States , the American dollar is used as the standard unit of currency in international markets for commodities such as gold and petroleum ( the latter , sometimes called petrocurrency , is the source of the term petrodollar ) . Some non-U.S. companies dealing in globalized markets , such as Airbus , list their prices in dollars .   The U.S. dollar is the world 's foremost reserve currency . In addition to holdings by central banks and other institutions , there are many private holdings , which are believed to be mostly in one-hundred-dollar banknotes ( indeed , most American banknotes actually are held outside the United States ) . All holdings of U.S.-dollar bank deposits held by non-residents of the United States are known as `` eurodollars '' ( not to be confused with the euro ) , regardless of the location of the bank holding the deposit ( which may be inside or outside the U.S. ) .   Economist Paul Samuelson and others ( including , at his death , Milton Friedman ) have maintained that the overseas demand for dollars allows the United States to maintain persistent trade deficits without causing the value of the currency to depreciate or the flow of trade to readjust . But Samuelson stated in 2005 that at some uncertain future period these pressures would precipitate a run against the U.S. dollar with serious global financial consequences .