bit / byte
Many people wonder where these two computer terms come from. Of the two, bit is older, dating to 1948. It first appears in A Mathematical Theory of Communication by C.E. Shannon in Bell Systems Technical Journal in July and October of that year. (This paper is one of the seminal works of modern information theory. The fact that it is the first known use of bit is simply a footnote to its scientific importance.) In the paper, Shannon credits a J.W. Tukey with the coinage:
The choice of a logarithmic base corresponds to the choice of a unit for measuring information. If the base 2 is used the resulting units may be called binary digits, or more briefly bits, a word suggested by J. W. Tukey.
As Shannon indicates, bit is an abbreviated form of binary digit, chosen probably because it is also a play on the meaning of the then existing word bit signifying a small part.
The term byte is of less certain origin, but probably was coined by someone at IBM (perhaps a Dr. Werner Buchholz) around 1964. The word byte is a play on bit. The original sense of the term was the amount of data required to represent one character—usually, but not always, eight bits. Over time, the predominant sense shifted to mean eight bits exactly.
Some have suggested that it is an abbreviation for BInary digiT Eight and that the Y was substituted for the I so to prevent typographical confusion with bit. Another suggestion is that it is from BinarY TErm. Neither of these claims is well substantiated and are probably false.
Also playful, but less well known, is the term nybble or nibble, meaning half a byte, or four bits.
(Sources: Oxford English Dictionary, 2nd Edition; Safire’s Quoth the Maven; Carver’s A History of English in Its Own Words)
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Copyright 1997-2007, by David Wilton
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"Nybbles and Bits”
No, “Nybbles and Bits” is not a call to my dog Reesie that it is time to eat. Chicago, 1967—I was teaching computer programming part-time at Harvard Automation Business College (a private trade school with a fancy name) to supplement the miserly salary IBM Corporation paid engineers in those days. We were into the early weeks of a introductory course in computer technology that I had developed the curriculum for. It was my profound belief that to be an acceptable programmer the student needed to have a good understanding of what went on inside the hardware of a computer at least functionally. She or he needed to know and understand the machine language instructions, what the bussing structure was, etc. I happen to be speaking about bits and bytes when a pretty young thing in the front row popped off the question, “If eight bits is a byte then what is four bits or half a byte?” It caught me off guard and the smirk she had on her face thew me for a second. I fired back without a second thought, “If eight bits is a byte then four bits is a nybble.” The class broke up and the smirk she had wore left her face. I had never heard of the term before; at IBM, in any journal of the IEEE, the ACM, any trade magazine or any where else; it was just a spur of the moment thing. A lot of things happen or come to one at the “spur of the moment.” Sometimes we act on them, at other times we don’t. Sometimes it is good when we do, sometimes it is good when we don’t. “Kibbles and Bits” and “Nybble” are part of our urban vocabulary today. This certainly was not true 40 years ago. Does adding yet another word to the common English language database count toward murdering the King’s English? If I were schizophrenic I’d worry.
James D. Petros