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Comment by derekp7 | Hacker News Reader

I think this comes down to, does a device need to be Turing complete to be considered a computer? If not, then what level of complications is needed for it to be a computer? For example is a watch, or a record player, a computer?

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A Turing machine is a subset of computers.

http://etymonline.com/index.php?term=computer&allowed_in_fra...

The level of complication necessary is "can compute stuff". Whether you want to include any kind of functional transformation as a computation or not is up to you.

I don't know that it needs to be Turing complete, but I'm inclined to say that it should have at least some control operations to qualify as a computer.

Example: Consider a hypothetical machine that implements standard SQL in hardware. Such a device would not be Turing-complete. Would you still call it a computer? I would.

IMHO as long as it has states, and it actually accepts some input while rejecting others, it is a computer. http://en.wikipedia.org/wiki/Theory_of_computation

EDIT: Thus a printer IS a computer, not for the procedural operations, but for that you can feed in some illegal input through the interface(no matter serial, peripheral or USB), and it will either send you back some complaint, or disconnect from you, or burn itself down.

But can you feed this pinoccoscribe illegal input?

Probably not, since the correct response to illegal input is to never arrive at a halting state, and putting aside mechanical considerations, it doesn't seem like the boy is supposed to loop over anything in such a way that would allow it (in intention, not in practice) never to halt.

Not 'but' but 'and' right?

Computer: an electronic device which is capable of receiving information (data) in a particular form and of performing a sequence of operations in accordance with a predetermined but variable set of procedural instructions (program) to produce a result in the form of information or signals.

I disagree with the "electronic" part. That disqualifies Charles Babbage's early mechanical computers, not to mention all of biological/chemical computing.

And the electro-mechanical computers of the 40s and 50s.

How do you separate the data from the instructions in this case? I'd say it's the same thing. You can change the word, but not how a word is translated into hand movements without rebuilding the whole thing (please don't!). Isn't the word configuration more like input, than a program?

On the other hand, this definition is very vague...

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