The computer: a definition.

So what is a computer versus a caluclator, or a programmable controller? Actually this is very simple, until you disagree with the definition and insert religion... A computer is a programmable computing system that can run pre-prepared 'software'. A masked programmed microprocessor ~probably~ is not a computer (the STAMP is clearly an exception here). A programmable calculator generally is ~not~ a computer, although advanced ones with mass storage and off-the shelf applications programs clearly IS a computer. So is the fuel injection processor chip in your car a computer? Clearly not. How about a HP-41? Clearly this meets the above definition, as it has applications programs available. Ok, what about a HP-33? Hmm, probably a programmable calculator, by the above definition. What about a PLC (programmable logic controller)? Clearly not a computer, no software as such, and its not primarily a computational device, its really just a fancy state machine. While any definition will leave some grey areas, this definition seems a bit clearer than most.