An Old Univac Ad: “You’re Trying to Divide by Zero”

Here’s a computer ad from 1956 – it’s for Univac computers, a brand name that was as synonymous with “computer” in the same way that “Xerox” was once synonymous with “photocopier”:

Old Univac ad: "You're Trying to Divide by Zero"
Click the ad to see it at full size.
Ad courtesy of Miss Fipi Lele.

Here’s the text of the ad. If it seems a little strange to your modern sensibilities, it’s because it’s ad copy from the era of Mad Men — that’s just how advertising was back then. Note that lack of technical jargon or specs, neither of which would’ve been useful back then, when very few people would’ve known what they meant:

“You’re Trying to Divide by Zero”

A scientist, testing a formula on Univac recently, was amazed to see the computing system stop, then automatically type the reproof: “You’re trying to divide by zero.” A quick check proved that Univac, as always, was right.

This graphic demonstration points out just one of the many Remington Rand refinements in the art of computer programming and operation. For Univac has been trained to spot human errors. It can now carry out commands given in simple business English. It can even manufacture its own program of instructions automatically – at electronic speeds, with unparalleled accuracy.

These skills have been developed as a direct result of Univac’s unique position in the field of electronic data-processing. Because, with every Univac delivered goes 10 years’ experience in electronic computing…5 years’ experience in the commercial type of data-processing. This wealth of background in programming and operation is unobtainable elsewhere.

The unprecedented savings of Univac data-processing have been proved by solving actual consumer problems – not by working out theoretical solutions with non-existent computers. You can be sure that, when you install the Univac, you’ll get under way faster, surer and more economically because the System has already handled similar work.

Univac is now at work in leading organizations throughout the country. And, in today’s competitive market, the company which cuts its overhead first comes out on top. So don’t wait until 1957…1958…or 1959 to cash in on the tremendous savings available to you now with the Remington Rand Univac System.

Some observations:

  • Error messages: while old hat to even modern laypeople, must’ve seemed like a great leap forward back then.
  • “Univac, as always, was right.” Can you imagine even Apple’s blowing-sunshine-up-your-ass ads making that claim about their machines today?
  • “It can now carry out commands given in simple business English.” I’m guessing that they mean COBOL. One era’s technological wonder is another era’s coding horror.

    [Update: Looks like I got my programming language timelines wrong. “mistercow” points out on Reddit that COBOL didn’t appear until 1959 and suggests that the “commands in simple business English” language is probably FLOW-MATIC, one of COBOL’s predecessors.]

  • “…with every Univac delivered goes 10 years’ experience in electronic computing…5 years’ experience in the commercial type of data-processing". These short timeframes may seem quaint, but keep in mind that the concept of what is computable isn’t even 100 years old yet. You should also note that web applications are only slightly older than 10 years and that XMLHttpRequest, which makes Ajax possible, turns ten in the new year (it was released by Microsoft as an ActiveX object for Internet Explorer 5 for Outlook Web Access in 1999).

And finally, two things that a programmer in today’s economy should keep in mind. It’s almost as if they’re special messages sent through time:

  1. “The unprecedented savings of Univac data-processing have been proved by solving actual consumer problems – not by working out theoretical solutions with non-existent computers.”
  2. “…in today’s competitive market, the company which cuts its overhead first comes out on top.”

Although these statements were made back when computers were rare and extremely expensive and well before there was a computer on every office desk – in fact, well before computers could even fit on desks – they hold true today. If you’re a programmer looking to make a living in 2009, it’ll pay to develop applications that solve actual problems and either help people make money or save it. To borrow a line from Don Dodge at Startup Empire, make sure your applications are aspirin (must-haves), not vitamins (nice-to-haves)!

25 replies on “An Old Univac Ad: “You’re Trying to Divide by Zero””

I think you’ve got that last line backwards: vitamins are must-haves, and asprin is a nice-to-have.

@Anonymous: You’ve got a point: if you’re using the term “vitamins” to refer to the nutrients in food, then vitamins are indeed a must-have and aspirin is a nice-to-have.

I think Dodge was using “vitamins” in the “vitamin supplement pills” sense, which is the sense used in his metaphor. From a “pills” point of view; I’ll pick aspirin over vitamins any day; you can get your vitamins by eating right.

And just remember, all of those early Univac computers were made entirely of vacuum tubes. Thousands of them.

It’s not fair to liken an old (and not likely known) synonym with another old (and not likely known) synonym – ‘in the same way that “Xerox” was once synonymous with “photocopier”’. What if your readers are young eh?

Never mind that I can’t come up with a better example myself (maybe post it notes?)…

@Anon: You may have a point there. I guess that’s my old-fart-ness showing.

When I was a kid, people would refer to “getting Xeroxes” of a document. Perhaps I should’ve said “the way ‘iPod’ is synonymous with ‘MP3 player’.”

No, they were solid state by this time. Only the first couple of experimental computers in the 1940s tried to use vacuum tubes.

How many of you have forgotten that Xerox made mainframe computers? A Xerox mainframe was “the computer” at my university in 1976.

Univac made a “Solid State” computer by about 1956, but it was intended to compete with the (tube) IBM 650 and with card-based Tab equipment. I owned one, some time ago. Long story. Anyway, the one in the picture looks more like a “Univac” (no model number or name), the original, which indeed used tubes, lots of them. Of course, even the Univac Solid State90 (mine) had some tubes, including over 60 Thyratrons, in the printer.

Transistors did replace tubes fairly quickly, but a bit later. And there were definitely many production machines based on tubes (e.g. IBM 701, Univac, Bendix/CDC G-15…)

Here, the graphic depicts a keyboard and a screen in 1956?? Wouldn’t work for ’66. Mohawk Data Sciences invented keyboard input in late 60s and the first real screen I ever saw was about 1983 and cost $9,000 through Compugraphics.

You must have an aspiring when your head aches, it is a solution to a real problem. Vitamins, on the other hand, don’t solve any problems directly. It would be nice to have some, but you don’t feel as if you must have some.

Hell, I liked COBOL. I could code the hell out of anything with COBOL and a little Assembler mixed in for a moment of speed. I miss using my hex calculator! And then those great chip assembler codes and instruction sets when the litlle machines came in. Full control. Now it’s a bunch of C++ wimps I gotta deal with.

Most of the comments on the UNIVAC ad had an historic perspective. For me it was nostalgic. In addition to those many electron tubes, not thousands, there were two, I think, drums containing twelve thousand little pools of mercury. Each pool carried the coding for one alfa-numeric charicter as a soulnd wave. This was for its figurative fifteen minutes of fame, the great breakthrough in storage. The large pictured storage cabinet had its own air conditioning. This perk provided storage for your brown bag, when you were on the midnight shift.

Joey — my friend just discovered a “divide by zero” error in his new Nikon P6000 (which is how I ended up on your blog). Turns out that when the built-in GPS in the Nikon can’t determine location (no sat coverage, whatever), it sets the lat/long to 0. But not just 0 or 0.0, but 0/0. I don’t know how those jackasses didn’t think that’d be a problem but apparently when Phanfare (the photo-hosting site my buddy and I use) tries to parse the geodata in order to provide a nice pop-up Google map for the photo, it barfs.

Anyways, I read your blog years ago (likely following a link from BB), and it was nice to reacquaint myself with your more recent writing.

To Bill Meers: that isn’t a screen. It is a built in keyboard with a blank area for placing papers above it. If you look at other pictures of the Univac system (like the ones with Cronkite during the 1952 election), there was an additional typewriter-like device (like the one on the right in the picture above) that would be used for printing short messages. The other typewriter-like device (on the left) is probably a key-to-tape data entry machine (like a keypunch machine).

There are lots of pictures and pdf’s of old documentation on the Univac and other old systems at

One thing I noticed from the documentation: the high speed printer was fed output from a tape drive, not from the CPU. Reading, writing and buffering was handled by two cabinets of hardware. So, the tape drive, printer and two big boxes behind them in the picture above has been replaced by a laser printer fed output via a wire directly from the computer, all of it driven by software now! Wow, miniaturization!

Leave a Reply

Your email address will not be published. Required fields are marked *