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Re: Answer about bits and bytes



Dan Harmon <[email protected]> writes:
> Just a note, Jim's attribution dates seem to be older than yours. Not
> that it matters a whole hill of beans.

Nope, Jim sited a PDP-10 manual from 1971, and the first edition of _The Art of
Computer Programming_ came out in 1967. (I quoted the second edition, but I
know that the first edition had MIX too.)

The book _IBM's Early Computers_ by Bashe, Johnson, Palmer, Pugh says the
following about the STRETCH system developed in 1956 (akin to 704 and 705):
"In July, Stretch technical staff manager Buchholz wrote a report listing the
advantages of a word length of sixty-four bits. Assuming an _m-bit binary field
for addressing a sixty-four-bit memory-contained word, he noted, _m+1 bits
could address a half-word, _m+2 bits a quarter-word, _m+3 bits an eight-bit
segment, and so on until _m+6 bits could address a single bit. Using this
systematic addressing principle, one class of instructions could address words,
and other classes could address shorter operands by increasing the length of an
address field. By this time, the term "byte" had been coined as a way of
avoiding typographical confusion between bit and "bite", a term that project
personnel had been using to designate small, character-oriented word segments.
The sixty-four-bit format was adopted in September; like the previous format of
sixty bits, it was accompanied by redundant bits for use by error-detection and
-correction circuits."

They footnote: Also see W. Buchholz, January 1981: "Origin of the Word Byte",
_Annals _of _the _History _of _Computing 3, p. 72, which explains how "byte"
later came to imply eight bits.

P.S. The _Barron's Dictionary of Computer Terms_ says:

BYTE A byte is the amount of memory space needed to store one character,
which is normally 8 bits. ...

(Wondering what the cryptographic relevance of all this might possibly be...)

---

<a href="mailto:[email protected]">Dr. Dimitri Vulis</a>
Brighton Beach Boardwalk BBS, Forest Hills, N.Y.: +1-718-261-2013, 14.4Kbps