[Altair 8800]

Altair was not the first personal computer but...

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The Altair is NOT the first computer but....

Those of us who work on computers of the 1970's, know that the MITS Altair 8800 was not the "first" personal computer, when it came out in 1975. It was important but not the very "first". (For some of my discussion about the origins of the MITS Altair - it's name and how it led to an early microcomputer standard, the S-100 bus - see this Web page.)

But on Oct 2007, I saw Doug Salot's "blinkenlights" Web site about old computers, when I found a "riddle me this.." kind of page on the question, "what was the first personal computer?" It's an amusing and informative page. But the entry for the MITS Altair 8800 disappointed me a little:

"Was it the MITS Altair?

You're way off! The Altair, introduced in January 1975, was the first computer to be produced in fairly high quantity, and it was the first computer to run Microsoft software, but we're not sure that's a good thing.

Unfortunately for computer history buffs, the Altair is often mistakenly called the first personal computer by Microsoft-loving journalists who don't know any better. "

This is what I wrote to the site's author:

The somewhat popular notion that the Altair 8800 is the "first" personal computer, is not simply due to what you call its "Microsoft software" connection. It's because this computer has many claims to starting the modern microcomputing industry. MITS and their Altair have several distinctions over other early computers; and it has more direct relevance to today's personal computers that you suggest.

1) The Altair was produced in quantity as you point out, probably several thousand in various versions. Still, not enough were produced to satisfy demand for early Altairs.

2) It used the Intel 8080 processor, which was the earliest microprocessor to be used in many subsequent microcomputers. (The 8008 was only used in a few general-purpose computers systems, and was generally used as a controller in terminals, cash registers, etc.) Intel-based microcomputers became dominant to the present day.

3) It used a 100-pin bus, which was the FIRST bus to be copied EXTENSIVELY by other microcomputer companies - starting with IMSAI. That became the "S-100 bus" which was used by over 100 companies over the subsequent decade or more. (Other busses were copied as well, such as the SWTP SS-50 and the Apple II expansion bus, but they came later.)

4) None of those considerations mention "Microsoft", but it's a fact of history that Microsoft BASIC was developed for use on the Altair 8800, and that product founded the company.

5)...however, another S-100 company, IMSAI, who built the first and very successful "clone" microcomputer of the Altair 8800, had a leading role in working with another software developer. Dr. Gary Kildall worked with IMSAI to develop an operating system called IMDOS, based on his operating system which he called CP/M. Digital Research's CP/M 1.4 product, based on his IMSAI work and prior work, was the first of what became a dominant operating system for 1970's Intel-based microcomputers. Digital Research was a strong player even after the IBM PC and its Microsoft MS-DOS entered the market in 1981.

6) The net effect of the S-100 and CP/M market was to set standards for open and expandable hardware, and for a common and open set of software tools and operating systems. The IBM PC in 1981, simply put, was designed to compete in that market ON THOSE SAME TERMS. (IBM's prior "personal computing" products were proprietary and "closed". They did not succeed like the IBM PC.)

In summary, therefore, I'd call the MITS Altair 8800 the first standard-setting, production quantity, and popularly successful microprocessor-based personal computer.

By those terms, I mean that it initiated or supported a number of industry-leading companies; Intel, Digital Research, Microsoft. It led to the founding of hundreds of software and hardware companies which built and sold products based on Altair-compatible systems. These subsequent systems and products created an industry, into which IBM was then able to introduce their IBM PC. That system started the next round of standards and products which continue to the present day.

Earlier products, including those mentioned on your Web page, were not as successful or popular on these terms. But each of them played some role in the overall evolution of personal use of computing devices and systems. I'm glad your page includes them. But please give the MITS Altair more credit than being a platform for Microsoft.

Herb Johnson
"Dr." S-100

Doug responds..

Doug was kind enough to respond promptly to my email, as follows:

Herb, if you click the altair image on my home page, you'll see I do give the machine a little more credit: [It's a nice history of MITS and the Altair line.]

I created the "first pc" page in frustration one night about 8 years ago. I was active on the "classiccmp" mailing list, and the altair kept coming up as the "frist pc" -- it was prized by newbie collectors, bid up on ebay, etc. Those who actually used an altair remember it as a very flakey machine.

Anyway, I wrote the page with the intention of shifting some of the lime light away from the altair and towards several other equally or more innovative (and earlier) machines.

Personally, I think a machine like the HP 9830 is a much more interesting computer and much more robust, but I freely admit that the altair got a lot of people interested in the hobby, and has an important place in history.

If I ever get around to updating the site, I may include your note as a counter argument. But the page is mostly intended to show that the idea of "first" is ambiguous, and there are plenty of candidates for the title.

Cheers, Doug

..my reply

I agreed to exchange quotes on our pages. Also, I replied that the flakiness of the Altair 8800 is generally acknowledged. It's usually described in this way: "the IMSAI was a better design". But people have working Altairs 8800's to this day, or can repair them. Here's what else I said:

"We can argue about whether S-100 and CP/M and the 8080/Z80 markets were merely "major" or "dominant", but not about their significance. I often think about a comparison to Henry Ford's Model T. Ford did not invent the automobile. What he did was to produce a standardized product, in quantity, which was affordable, at a time when cars were not. Sound familiar??

As for Microsoft: keep in mind that before the IBM PC, Microsoft was a software LANGUAGE company. They sold BASIC, which in some forms could run stand-alone and open and close files and such. But it was not an operating system: CP/M WAS. And many other OS's of the period were CP/M like or compatible. That includes MS-DOS, by function and feature.

I have a substantial history of DRI on a section of my Web site at this link; and the IMSAI chapter of CP/M development is at this link.

So, please consider adding a bit to your Altair page. It led directly to the IMSAI, which was a major player in DRI's CP/M development - and CP/M was important. The S-100 bus was not merely a "standard", it was the bus design for over a hundred manufacturers of early 1970's systems, before technology could put a "personal" computer onto one card - and before there was much "personal" software to run! I guess I'd call CP/M and S-100 open architecture (and Microsoft BASIC, if you insist) the "bedrock" upon which modern personal computing was built.

And...grumble...I'll think about adding "Microsoft BASIC" to my Altair Web page.... "

Herb Johnson

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Herb Johnson
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