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From: Douglas McIlroy <douglas.mcilroy@dartmouth.edu>
To: TUHS main list <tuhs@tuhs.org>
Subject: [TUHS] Re: Does anybody know the etymology of the term "word" as in collection of bits?
Date: Thu, 8 Sep 2022 21:33:42 -0400	[thread overview]
Message-ID: <CAKH6PiWYQUXKdARUy_cHWqpiJQzEgSr2t4UGc7fmgF8j9ygpLg@mail.gmail.com> (raw)

 > I heard that the IBM 709
> series had 36 bit words because Arthur Samuel,
> then at IBM, needed 32 bits to identify the playable squares on a
> checkerboard, plus some bits for color and kinged

To be precise, Samuel's checkers program was written for
the 701, which originated the architecture that the 709 inherited.

Note that IBM punched cards had 72 data columns plus 8
columns typically dedicated to sequence numbers. 700-series
machines supported binary IO encoded two words per row, 12
rows per card--a perfect fit to established technology. (I do
not know whether the fit was deliberate or accidental.)

As to where the byte came from, it was christened for the IBM
Stretch, aka 7020. The machine was bit-addressed and the width
of a byte was variable. Multidimensional arrays of packed bytes
could be streamed at blinding speeds. Eight bits, which synced
well with the 7020's 64-bit words, was standardized in the 360
series. The term "byte" was not used in connection with
700-series machines.

Doug

             reply	other threads:[~2022-09-09  1:35 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-09  1:33 Douglas McIlroy [this message]
2022-09-09  2:12 ` Larry McVoy
2022-09-13 14:23   ` John Foust via TUHS
2022-09-09  2:45 ` George Michaelson
2022-09-16  5:55 ` Marc Donner
  -- strict thread matches above, loose matches on Subject: below --
2022-09-11 13:30 Douglas McIlroy
2022-09-11 15:08 ` John Cowan
2022-09-11 15:30 ` Bakul Shah
2022-09-11 15:45   ` Paul Winalski
2022-09-11 16:20     ` Steve Nickolas
2022-09-09 19:39 Nelson H. F. Beebe
2022-09-09 20:27 ` Bakul Shah
2022-09-09 21:12   ` Henry Bent
2022-09-09 21:44   ` Dave Horsfall
2022-09-09 18:46 Norman Wilson
2022-09-10  1:35 ` Paul Winalski
2022-09-09 17:26 Douglas McIlroy
2022-09-08 21:16 Noel Chiappa
2022-09-08 21:24 ` Dan Halbert
2022-09-08 18:20 Noel Chiappa
2022-09-08 19:28 ` Jim Capp
2022-09-08 16:51 [TUHS] " Jon Steinhart
2022-09-08 16:56 ` [TUHS] " Andrew Hume
2022-09-08 17:28 ` Dan Halbert
2022-09-09  0:00   ` Greg 'groggy' Lehey
2022-09-09 15:49     ` Paul Winalski
2022-09-09 18:44       ` Bakul Shah

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