Overview
The name Thaler (from German thal, or nowadays usually Tal, "valley", cognate with "dale" in English) came from the German coin Guldengroschen ("great guilder", being of silver but equal in value to a gold guilder), minted from the silver from a rich mine at Joachimsthal - Jáchymov (St. Joachim's Valley) in Bohemia (then part of the Holy Roman Empire, now part of the Czech Republic).
For further history of the name, see Dollar.

Etymology
The colloquialism buck is often used to refer to dollars of various nations, including the U.S. dollar. This term, dating to the 18th century, may have originated with the colonial fur trade. Greenback is another nickname originally applied specifically to the 19th century Demand Note dollars created by Abraham Lincoln to finance the costs of the Civil War for the North. The original note was printed in black and green on the back side. It is still used to refer to the U.S. dollar (and not to the dollars of other countries).
Grand, sometimes shortened to simply G, is a common term for the amount of $1,000. The suffix K (from "kilo") is also commonly used to denote this amount (such as "$10K" being pronounced "Ten kay" to mean $10,000). Banknotes' nicknames are usually the same as their values (such as five, twenty, etc.) The $5 bill has been referred to as a "fin" or a "fiver" or a "five-spot", and the $10 bill as a "sawbuck", a "ten-spot", or a "Hamilton", the $20 Bill as a "double sawbuck" or a "Jackson", the $1 bill is sometimes called a "single", the $2 bill a "deuce" or a "Tom" and the $100 bill is nicknamed a Benjamin, or "Benjie" (after Benjamin Franklin, who is honored on the note) or a C-note (C being the Roman numeral for 100)or a Century Note. Occasionally these will be referred to as "dead presidents", although neither Hamilton ($10) nor Franklin ($100) was President. $100 notes are occasionally referred to as 'large' in banking ("twenty large" being $2,000, etc.). The newer designs are sometimes referred to as "Bigface" bills.
In Panama, the translation of buck is palo (lit. stick); a nickname for the balboa (dollar). For example: Esto vale 20 palos ("This is worth 20 bucks").

Nicknames
See also: History of the United States dollar
The first dollar coins issued by the United States Mint were of the same size and composition as the Spanish dollar and even after the American Revolutionary War the Spanish and U.S. silver dollars circulated side by side in the United States. However, various English colonies were also used, including the lion dollar..
For articles on the currencies of the colonies and states, see Connecticut pound, Delaware pound, Georgia pound, Maryland pound, Massachusetts pound, New Hampshire pound, New Jersey pound, New York pound, North Carolina pound, Pennsylvania pound, Rhode Island pound, South Carolina pound and Virginia pound.

History
See also Continental currency
In 1775, the United States and the individual states began issuing "Continental Currency" denominated in Spanish dollars and (for the issues of the states) the £sd currencies of the states. The dollar was valued relative to the states' currencies at the following rates:
The continental currency suffered from printing press inflation and was replaced by the silver dollar at the rate of 1 silver dollar = 1000 continental dollars.

Continental currency
From 1792, when the Mint Act was passed, the dollar was pegged to silver and gold at 371.25 grains of silver, 24.75 grains of gold (15:1 ratio). 1834 saw a shift in the gold standard to 23.2 grains, followed by a slight adjustment to 23.22 grains in 1838 (16:1 ratio).
In 1862, paper money was issued without the backing of precious metals, due to the Civil War. Silver and gold coins continued to be issued and in 1878 the link between paper money and coins was reinstated.
In 1900, the bimetallic standard was abandoned and the dollar was defined as 23.22 grains of gold. Silver coins continued to be issued for circulation until 1964, when all silver was removed from dimes and quarters, and the half dollar was reduced to 40% silver. Silver half dollars were last issued for circulation in 1969.
Gold coins were withdrawn in 1933 and the gold standard was changed to 13.71 grains, equivalent to setting the price of 1 troy ounce of gold at $35. This standard persisted until 1968. Between 1968 and 1975, a variety of pegs to gold were put in place. 1975 saw the U.S. dollar freely float on currency markets.
Official United States coins have been produced every year from 1792 to the present. In normal circulation today, there are coins of the denominations 1¢ ([One] Cent, also referred to as a Penny), 5¢ (Nickel), 10¢ (Dime), 25¢ (Quarter Dollar officially, or simply Quarter in common usage), 50¢ (Half Dollar; uncommon), and $1 (Dollar; uncommon). Federal Reserve Notes exist as $1, $2 (uncommon), $5, $10, $20, $50, and $100 denominations. Previously to 1934 there were also $500, $1000, $5000, $10000, and 7 $100,000 bills made. According to http://www.highdenomination.com/Gold_Details.asp?id=904 there were 42,000 $100,000 notes printed, all of which were gold certificates and are accounted for. They were never intended for general circulation and are illegal to own.
Dollar coins have not been very popular in the United States.
The United States has minted other coin denominations at various times from 1792 to 1935: half-cent, 2-cent, 3-cent, 20-cent, $2.50, $3.00, $5.00, $10.00, $20.00 and $50.00. Technically, all these coins are still legal tender at face value, though they are far more valuable today for their numismatic value, and for gold and silver coins, their precious metal value. In addition, an experimental $4.00 coin was also minted, but never placed into circulation and is properly considered to be a pattern rather than an actual coin denomination. The $50 coin mentioned was only produced in 1915 for the Panama-Pacific International Exposition (1915) celebrating the opening of the Panama Canal. Only 1,128 were made, 645 of them were octagonal; this remains the only US coin that was not round as well as the largest and heaviest US coin ever.
In the 1936 to present period the only denominations produced for circulation have been the familiar penny, nickel, dime, quarter, half dollar and dollar. (The nickel is the only coin we use today that is essentially unchanged (except in its design) from its original version. Every year since 1866 our nickel has been 75% copper and 25% nickel, except for 4 years during World War II when nickel was needed for the war.) Since 1982 the United States Mint has also produced many different denominations and designs specifically for collectors and speculators. The rest of this paragraph briefly mentions some of these coins. There are silver, gold and platinum bullion coins, called "American Eagles," all of which are legal tender though their use in everyday transactions is non-existent. The reason for this is that they are not intended for use in transactions and thus the face value of the coins is much lower than the worth of the precious metals in them. The American Silver Eagle bullion coin is issued only in the $1 (1 troy ounce) denomination. The American Gold Eagle bullion coin denominations (with gold content) are: $5 (1/10 troy oz), $10 (1/4 troy oz), $25 (1/2 troy oz), and $50 (1 troy oz). The American Platinum Eagle bullion coin denominations (with platinum content) are: $10 (1/10 troy oz), $25 (1/4 troy oz), $50 (1/2 troy oz), and $100 (1 troy oz). The silver coin is 99.9% silver, the gold coins are 91.67% gold (22 karat), and the platinum coins are 99.95% platinum. These coins are not available from the Mint for individuals but must be purchased from authorized dealers. In 2006 The Mint began direct sales to individuals of uncirculated bullion coins with a special finish, and bearing a "W" mintmark. The Mint also produces high quality "proof" coins intended for collectors in the same denominations and bullion content which are available to individuals.
The largest denominations of currency currently printed or minted by the United States are the $100 bill and the $100 troy ounce Platinum Eagle.

Silver and gold standards

Value
The minutes to the August 8, 2006 meeting, at which the Federal Open Market Committee kept short-term interest rates unchanged for the first time in more than two years, supported the view that U.S. borrowing costs have peaked. The dollar fell on the news on August 29, 2006, and has continued lower August 30, 2006, largely ignoring news the U.S. government has revised its estimate of second-quarter economic growth 2006 up to 2.9% from the initial 2.5%.

Factors influencing the price
This chart shows the amount of USD, in a particular year, that could purchase an equivalent amount of goods that were worth $1.00 in 1980.

Time-relative value
The dollar is also used as the standard unit of currency in international markets for commodities such as gold and petroleum (the latter sometimes called petrocurrency). Even foreign companies with little direct presence in the United States, such as the European company Airbus, list and sell their products in dollars, although some argue this is attributed to the aerospace market being dominated by American companies.
At the present time, the U.S. dollar remains the world's foremost reserve currency, primarily held in $100 denominations. The majority of U.S. notes are actually held outside the United States, known as eurodollars (not to be confused with the euro) regardless of the location. Economist Paul Samuelson and others maintain that the overseas demand for dollars allows the United States to maintain persistent trade deficits without causing the value of the currency to depreciate and the flow of trade to readjust. Milton Friedman at his death believed this to be the case but, more recently, Paul Samuelson has said he now believes that at some stage in the future these pressures will precipitate a run on the U.S. dollar with serious global financial consequences.
Not long after the introduction of the euro (€; ISO 4217 code EUR) as a cash currency in 2002, the dollar began to depreciate steadily in value. After the euro started to rise in value in March 2002, the U.S. trade and budget deficits continued to increase. By Christmas 2004 the dollar had fallen to new lows against all major currencies, especially the euro. The euro rose above $1.36/€ (under 0.74 €/$) for the first time in late December 2004, in sharp contrast to its lows in early 2003 ($0.87/€). In late May and early June, the U.S. dollar, with the advantage of Federal Reserve's policy of raising rates, rose significantly against all major currencies. The U.S. dollar broke almost all expectations in 2005 (some analysts previewed the dollar dropping as far as $1.60 per euro), finished the year with a significant double-digit recovery against the euro and Japanese Yen. However in 2006, the dollar again showed a double digit (11%) loss against the euro. This fall continued and the dollar hit a new record low in 2007 with 1.38 per euro.

International use

Main article: Reserve currency The dollar as the major international reserve currency

Main article: US Dollar Index US Dollar Index
Other nations besides the United States use the U.S. dollar as their official currency, a process known as official dollarization. For instance, Panama has been using the dollar alongside the Panamanian balboa as the legal tender since 1904 with a rate of change of 1:1. Ecuador (2000), El Salvador (2001), and East Timor (2000) all adopted the currency independently. The former members of the U.S.-administered Trust Territory of the Pacific Islands, which included Palau, the Federated States of Micronesia, and the Marshall Islands, chose not to issue their own currency after becoming independent, having all used the U.S. dollar since 1944. Two British dependencies also use the U.S. dollar: the British Virgin Islands (1959) and Turks and Caicos Islands (1973).
Some other countries link their currency to U.S. dollar at a fixed exchange rate. The local currencies of Bermuda and the Bahamas can be freely exchanged at a 1:1 ratio for USD. Argentina used a fixed 1:1 exchange rate between the Argentine peso and the U.S. dollar from 1991 until 2002. The currencies of Barbados and Belize are similarly convertible at an approximate 2:1 ratio. In Lebanon, one dollar is equal to 1500 Lebanese pound, and is used inter­changeably with local currency as de facto legal tender. The exchange rate between the Hong Kong dollar and the United States dollar has also been linked since 1983 at HK$7.8/USD, and pataca of Macau, pegged to Hong Kong dollar at MOP1.03/HKD, indirectly linked to the U.S. dollar at roughly MOP8/USD. Several oil-producing Gulf Arab countries, including Saudi Arabia, peg their currencies to the dollar, since the dollar is the currency used in the international oil trade.
The renminbi used by the People's Republic of China was informally and controversially pegged to the dollar in the mid-1990s at Y8.28/USD. Likewise, Malaysia pegged its ringgit at RM3.8/USD in 1997. On July 21, 2005 both countries removed their pegs and adopted managed floats against a basket of currencies. Kuwait did likewise on May 20, 2007,

Dollarization and fixed exchange rates

Exchange rates

Big Mac Index Suit by sightless over U.S. banknote design

Fiat currency
Gold as an investment
Silver as an investment
Category:Historical currencies of the United States
Where's George?
Economy of the United States