Is the Enigma a "computer"?

Further, what about the mechanical railway signalling frame, fitted with rotary interlocking. A computer? Maybe not, though probably the precursor to today's programmable logic controller...

I'd class Enigma as a "special purpose computer." It's actually not much different from Colossus in that they both did one job and were not really programmable (though Colossus could be programmed somewhat by re-wiring it).

Is an abacus a computer? Is a sextant a computer? The defination of a computer is a programmable, usually electronic, device that can store, retrieve, and process data. I'd say yes, go for it.

Doesn't an enigma machine fail this test then? Its programmability was severely limited and so far as I know its data storage and retrieval abilities were basically nonexistent.

Charles Babbage's mechanical computer, the Difference Engine?

You can see the BIOS Gear there, at the very bottom. Or is that the HAL, the Hardware Abstraction Layer?

-e

Oh, I love this (again, from the Wiki close-up of Babbage's Difference Engine): "Babbage never completed his difference engine, partly due to problems with friction (from management?) and machining accuracy (64-bit doubles not possible, sigh), but also because he kept changing the design. LMAO! WootWoot!

Does this sound (ever so slightly) a..er..bit familiar all you Bit Jockies out there? Bet Babbage was a friggin' Jolt junkie too. Programming Fuel.

-e

All he needed was meccano! I have seen a working model made from this great toy! If any one can find a link to the video, please post it!

Should the criteria for "computer" primarily consider whether or not the thingie actually computes? Whether it is programmable or not is secondary, I should think.

Nor is this criterion met only in hardware: During WW II, people who solved ballistic problems were called computers, and also such folk at Los Alamos who (themselves using Marchant calculators) computed slow-neutron capture rates for the various nuke core geometries under investigation. So, there you have it: people too can be computers. As this opens a can of (largely humorous) worms, perhaps we should constrain ourselves to computing machinery. Thingies, not people.

So maybe the primary criterion for "computer" should be: a device that computes, regardless of how such computation is realized in practice.

What say ye, thread?

-e

I think that's a good start, but you should be a little clearer about what you mean by "computes". Is computing simply the changing of input into a desired output through a predetermined algorithm? If that's the case then the Enigma machine qualifies.

A fair question. But let's look at this from another viewpoint: In the 1980s IBM built a specialized supercompter, the GF11, to solve a single problem: compute the mass of the proton from first principles. Consider this excerpt:

"In 1983, Weingarten left the University of Indiana to join IBM and build a computer specifically designed to run his QCD algorithms. He planned to build the fastest possible computer, a machine, he recalls, "big enough to get real numbers out of QCD - the biggest machine we could build and have any chance that we would get it to work." Along with Monty Denneau and a handful of other collaborators from the computer science department at Watson, Weingarten set out to design and build one of the world's first massively parallel supercomputers, with 566 processors. They called it the GF11, because they calculated that it would perform QCD calculations at roughly 11 gigaflops (a gigaflop is equal to 1 billion floating point operations per second). That would make the machine 40,000 times faster than the VAX computer Weingarten had been using at the University of Indiana, and 250 times faster than the fastest supercomputers then available, built by Cray."

Would the GF11 qualify, considering that it was implemented using a fixed, "pre-wired" program to take a single "input" (a model) and, after several years of CPU time (at 11 gigaflops, no less), generate a single output (a mass)?

Offhand, I would consider the Enigma a far more versatile computing machine than the GF11, all things considered.

-e

So maybe we need to add something like "supports a wide range of software" into our definition? That would seem to disqualify both the Enigma machine AND the GF11.

I tend to think not, mainly because, at least for me, the term "software" implies a specifc, particular kind of representation. The same operations could, for instance, be performed by hardware which does not use "software" (not even as "firmware") at all, in any sense of the word. Certainly analog computers have no concept of "software;" particularly mechanical analog computers. Here you find devices that most definitely compute things (and pretty complex things, too) and in which might be found such mechanical gems as precision differentials and ball-and-disk integrators, for example.

Perhaps this Wiki may be of some guidance, seeing as this problem is mainly one of definition.

-e

Nawwww, I'm going to be different and say its not a computer... its more of a hardwired programmable switching array.

Why not include Babbage's mechanical calculating engine?

Or besides the colossus how about the precurser to it the 'Bombe' (I think it was called).

'its more of a hardwired programmable switching array.'

Yep - that sounds like a computer alright!

Yeah, but you could also define an aqueduct as "a system to get water from a reservoir to a location where it is usable." Does this mean a bucket was the first aqueduct? What about a cupped pair of hands?

My point being: you can make the definition of something general enough to encompass many many things that wouldn't be included in a better definition.

I read in a recent report that Collosus was considered to be the first true "electronic" computor as it used valves as the sole means of computing. Previous so called versions used relays and were electro mechanical or just mechanical aids.

This article is quite fascinating...

-e