"Personal" Computers (Was: Details about IBM's early 'scientific' computers)

Rick Bensene rickb at bensene.com
Wed Nov 15 16:39:34 CST 2017

I wrote:

>> While the definition of the term "personal computer" varies depending

>> on who is using the term, these machines, and others like them, were 
>> designed to be used at a much more personal level than the
>> mainframe machines housed in the glass-walled rooms where only
"special" people were allowed
>> anywhere near them.

To which, Rich A. replied:

>This, like "Multics never got out of the lab", is a bogo-meme.
(Thanks, Neil!)
> People did not *need* to get near the mainframes in order to do their
jobs, unlike the jobs for which the small systems 
> (and you forgot the PDP-11 in your list) were created.  Most
programming on mainframes was special purpose, batch oriented, data
>processing connected to accounting systems (GL/AP/AR/PR), and a lot of
the rest was high intensity engineering (where at this level >even
physics is engineering) which needed lots of data handling for short

Yeah...I can agree with that.  But, part of the talk was about getting
"up close" with the computer, at a personal level - hands-on.
The glass-walled room machines weren't that way, and thus weren't
considered "personal computers", for just the reason you mentioned --
the work typically done on them was of a different class of work that
didn't require any kind of hands-on activity with the machine (except
for the operators, who loaded up the jobs, managed the tapes, and
gathered the printouts).   

The discussion had gone from talk about the IBM 709/709X computers,
which were more "glass room" type machines, to discussion about personal
computers.  I suffered some angst over the discussion of machines like
Apple IIs or even Altair 8800's as the first personal computers, when in
fact, the general term applied to computers that came long before these

Perhaps the glass-room meme isn't so much bogus, as it is a sign of the
cultural times.   In those days, the big machines were very expensive,
and required a lot of support --  that meant special power, air
conditioning, raised floors, and highly-trained people.   The
"management" of these big machine installations had a lot at stake...and
as such, they were very protective of their machines, which is most of
the reason they were encased in glass (they needed to be glass to be
able to show them off without letting people in...in the days, big
computer installations were class icons).   

It wasn't really so much that the work that the consumers (I wouldn't
use the word "users" to describe them, because they were never really
"using" the machine) of the results of the machines didn't need to have
access to the machines...it was more because the management only wanted
those who had all the necessary training and knowledge operating the
machines to assure the maximum amount of productivity for their
multi-million dollar investments to gain the best return on that
investment, as well as safety for these "delicate" machines.

As for the PDP-11, it was indeed a significant omission.  Honestly, I
ran out of time.  I missed the PB 250, which certainly should have been
on the list, and the PDP-11...and I'm sure that there are quite a number
of other machines that were missed.  

Compiling a full list of this class of machines, even during this
somewhat limited time period, would be a daunting process.    There were
many companies that popped up in the 1960s, along with those from
established computer makers,  that marketed small computers that were
generally intended to be used on a single-user basis, by individuals.
Examples off the top of my head are Computer Automation (PDC-808), Smith
Corona/Marchant SCM 7816, 3M (yes, the adhesive people) 2018, Control
Data 160/160-A, Digital Equipment PDP-1, HP 2100-series, Data
Acquisition Corp. DAC-512.....it could go on and on.  

I was writing my message as I was getting ready to head off to work, and
had to stop before I ended up being late.

Rick Bensene
The Old Calculator Museum

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