Monopoly money is a type of play money used in the board game Monopoly. It is different from most currencies, including the American currency or British currency upon which it is based, in that it is smaller, one-sided, and comes in different colors.
Many variations of Monopoly exist, with many types of money representing various currencies. In the more "standard" versions of the game, Monopoly money consists entirely of notes. Monopoly notes come in the following colors:
The modern Monopoly game has its Monopoly money denominated in $1, $5, $10, $20, $50, $100, $500, and (in some editions) $1000, with all but the last two paralleling the denominations in circulation in the United States. (The U.S. $500 bill and U.S. $1000 bill were withdrawn in 1969). Monopoly does not include a $2 bill; however, Monopoly Junior did include the $2 in addition to $3 and $4 denominations (which do not exist in U.S. currency) for many years. (Monopoly Junior later simplified its system to include only $1 bills.)
Fans have designed unofficial $1000 Monopoly bills for longer games and made them available online.
Special editions and spinoffs (e.g. Monopoly Deal) use larger denominations, as well as a Monopoly-specific currency symbol of a struck-through capital M.
"Monopoly money" is also a derisive term used in multiple senses. The most common is by countries that have traditionally had monochromatic currency (such as the United States) to refer to countries that have colorful currency (such as Canada). This has been used in places such as the "Weird Al" Yankovic song Canadian Idiot.
It can also be used as a derisive term to refer to money not really being worth anything, or at least not being used as if it is worth anything. This has been used when large companies trade securities amongst various entities to create fraudulent profits, and when governments such as Burma issue special currencies to foreign aid organization that cannot be traded on the free market and are therefore not really worth anything.