Bit (currency)
A bit was a unit of currency that existed in the form of a coin, which was used in California, United States of America on Earth during the late 19th century.

In 1893, after inadvertently traveling back in time, Lieutenant Commander Data asked a bellboy at the Hotel Brian for temporary lodging. The bellboy replied that it cost "six bits a day or four dollars a week." 

Later, when Data joined the local poker game, he was told that the ante was four bits. ()

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Earth currencies