A History of United States Paper Money
Recent Fraud Protection Innovations in Currency
Color Shifting Ink
A recent innovation in the currency world, the ink in some notes shifts color depending on the angle from which it is viewed. First issued in the United States in larger denominations in the 1990s, the denomination numerals in the lower-right corner on the obverse change from copper to green when the note is tilted.
Recently, some countries have included a hologram on some of their currency, creating a beautiful bill that cannot easily be forged.
Very tiny print adorns all legal tender paper notes in the United States today. Barely distinguishable with the naked eye, magnification is required to read letters printed into our designs.