History of paper money
Federal Reserve notes
Federal Reserve notes make up the majority of U.S. paper money in circulation today. The rest consists of U.S. notes and other currency still in circulation but no longer issued. The Bureau of Engraving and Printing (BEP), a division of the U.S. Treasury, prints Federal Reserve notes in denominations of $1, $2, $5, $10, $20, $50, and $100. Until 1946, it also printed $500, $1,000, $5,000, and $10,000 notes. These larger denominations circulated until 1969, when Congress discontinued them due to lack of use.
As the nation's central bank, the Federal Reserve issues, distributes, processes, and accounts for Federal Reserve notes in the United States and abroad. Congress passed the Federal Reserve Act in 1913, which mandated an elastic currency that would expand and contract based on public demand. The 12 regional Federal Reserve Banks, through their network of branches throughout the country, distribute Federal Reserve notes to the public through depository institutions. Federal Reserve assets are used as collateral for Federal Reserve notes in circulation. The Federal Reserve holds these assets chiefly in the form of U.S. Treasury, federal agency, and government-sponsored enterprise securities.
The U.S. Treasury issued demand notes in 1861 to finance the Civil War. Nicknamed "greenbacks" because of their color, they were the first paper currency to circulate in the United States after the Continentals (issued during the Revolutionary War). The following year, Congress authorized a new class of currency. Called United States notes—sometimes "legal tenders"—they ranged in denomination from $1 to $10,000. These notes, considered the first legal national currency, circulated alongside Federal Reserve notes until their issuance ended in 1971.
Other paper currency no longer in circulation includes national bank notes, which national banks issued from 1863 to 1935, and gold certificates, which the Treasury issued in exchange for gold coin and bullion. These notes circulated from 1865 to 1933. Silver certificates, authorized in 1878 and issued in exchange for silver dollars, accounted for nearly all of the $1 notes in circulation until November 1963, when the first $1 Federal Reserve notes were issued.
How currency is printed
The BEP prints Federal Reserve notes using a combination of traditional printing techniques and advanced technology.
The process begins with large, blank sheets of currency paper crafted from cotton and linen especially for the BEP.
The Treasury began redesigning currency in the 1990s. For the redesigned currency, the first step of the printing process adds the subtle background colors to the blank sheets using offset printing. The printed sheets dry for 72 hours before moving to the next step—intaglio printing.
Intaglio, which comes from the Italian word meaning "to cut or engrave," is what makes the intricate artwork on the note possible and gives U.S. currency its distinctive texture.
Images are engraved onto soft steel plates. When the ink is applied, it pools into the recessed areas of the plate. Paper is laid over the plate and the two are pressed together under 20 tons of pressure.
Each printing plate makes 32 copies of the bill being printed. Computers examine the large printed sheets for mistakes. After the sheets are cut into smaller sheets of 16, they move to letterpress, the third and final printing process. A letterpress overprints the Federal Reserve seal and its corresponding number designation, as well as the Treasury seal and serial numbers.
Last, the guillotine cutters separate the sheets into two sheets, then into individual notes, which are organized in "bricks" containing 40 packages of 100 notes each.
Initially, the BEP produced all U.S. currency in Washington, D.C., but in 1991 a second printing facility opened in Fort Worth, Texas.