Overview
The word bit is a colloquial expression referring to specific coins in various coinages throughout the world.
United States
In the US, the bit is equal to ¢. In the U.S., the "bit" as a designation for money dates from the colonial period, when the most common unit of currency used was the Spanish dollar, also known as "piece of eight", which was worth 8 Spanish silver reales. $ or 1 silver real was 1 "bit".
With the adoption of the decimal U.S. currency in 1794, there was no longer a U.S. coin worth $, but "two bits" remained in the language with the meaning of $. Because there was no 1-bit coin, a dime (10¢) was sometimes called a short bit and 15¢ a long bit. (The picayune, which was originally real or bit (¢), was similarly transferred to the US nickel.)
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