bit - technical definition

A small piece or quantity.
A contraction of the term binary digit, a bit is an individual 1 or 0 in a binary numeration system, a base 2 numbering system. So, a bit is the smallest unit of digital data.The word first appeared in print in 1948 in a paper written by Claude Shannon, who credited John Tukey, an early computer scientist at Bell Telephone Laboratories with coining the term in 1947. Tukey later wrote that the term evolved as an alternative to bigit or binit. See also binary and bit rate.
In coinage, originally a small silver coin worth one-eighth ( 1 / 8 ) of a Spanish peso. Later, a small British coin, a threepenny bit. Now commonly used to mean one-eighth ( 1 / 8 ) of a U.S. dollar, or twelve and a half (12 1 / 2 cents), usually in the phrases two bits ( 1 / 4 of a dollar, or 25 cents), four bits ( 1 / 2 of a dollar, or 50 cents), and six bits ( 3 / 4 of a dollar, or 75 cents). As the story goes, coins, especially small coins, were scarce in colonial America, so it was common practice to cut a bit (or two bits) off of a dollar coin to make change.

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