These machines can process photographs, set up your wireless, send emails, set up secure encipherment for on-line payments, do typography, refresh the screen, monitor the keyboard, manage the performance of all these in synchrony But the meaning of the word 'computer' has changed in time. In the s and s 'a computer' still meant a person doing calculations.
There is a nice historical example of this usage here. So to indicate a machine doing calculations you would say 'automatic computer'. In the s people still talked about the digital computer as opposed to the analog computer. But nowadays, it is better to reserve the word 'computer' for the type of machine which has swept everything else away in its path: But Alan Turing himself never made a point of saying he was first with the idea.
And his earnings were always modest. Picture from a Japanese graphic book of Turing's story. It didn't incorporate the vital idea which is now exploited by the computer in the modern sense, the idea of storing programs in the same form as data and intermediate working.
His machine was designed to store programs on cards, while the working was to be done by mechanical cogs and wheels. But more fundamental is the rigid separation of instructions and data in Babbage's thought. A hundred years later, in the early s, electromagnetic relays could be used instead of gearwheels. But no-one had advanced on Babbage's principle. Builders of large calculators might put the program on a roll of punched paper rather than cards, but the idea was the same: To see how different this is from a computer, think of what happens when you want a new piece of software.
You can download it from a remote source, and it is transmitted by the same means as email or any other form of data. You may apply an Installer program to it when it arrives, and this means operating on the program you have ordered. For filing, encoding, transmitting, copying, a program is no different from any other kind of data — it is just a sequence of electronic on-or-off states which lives on hard disk or RAM along with everything else.
The people who built big electromechanical calculators in the s and s didn't think of anything like this. I would call their machines near-computers, or pre-computers: Even when they turned to electronics, builders of calculators still thought of programs as something quite different from numbers, and stored them in quite a different, inflexible, way.
So the ENIAC, started in , was a massive electronic calculating machine, but I would not call it a computer in the modern sense, though some people do. I wouldn't call it a computer either, though some people do: But the Colossus was crucial in showing Alan Turing the speed and reliability of electronics.
It was also ahead of American technology. The ENIAC, of comparable size and complexity, was only fully working in , by which time its design was obsolete. Like Turing, Zuse was an isolated innovator. But while Turing was taken by the British government into the heart of the Allied war effort, the German government declined Zuse's offer to help with code-breaking machines.
Their work is influenced by the question: They conclude that the war hindered Zuse and in no way helped. But the significant development is that of a computer in the modern sense, designed from the start to be Turing-complete. This is what Turing and von Neumann achieved. They both saw that the programs should be stored in just the same way as data.
Simple, in retrospect, but not at all obvious at the time. The EDVAC report became well known and well publicised, and is usually counted as the origin of the computer in the modern sense. It was dated 30 June — before Turing's report was written. It bore von Neumann's name alone, denying proper credit to Eckert and Mauchly who had already seen the feasibility of storing instructions internally in mercury delay lines. This strongly contests the viewpoint put by Herman Goldstine, von Neumann's mathematical colleague, in The Computer from Pascal to von Neumann.
This is a great irony of history which forms the central part of Alan Turing's story. His war experience was what made it possible for him to turn his logical ideas into practical electronic machinery.
Yet he was the most civilian of people, an Anti-War protester of He was very different in character from John von Neumann, who relished association with American military power. But von Neumann was on the winning side in the Second World War, whilst Turing was on the side that scraped through, proud but almost bankrupt.
Martin Davis is clear that von Neumann gained a great deal from Turing's logical theory. But I would say that in Alan Turing alone grasped everything that was to change computing completely after that date: He knew there could be just one machine for all tasks.
He did not do so as an isolated dreamer, but as someone who knew about the practicability of large-scale electronics, with hands-on experience.
From experience in codebreaking and mathematics he was also vividly aware of the scope of programs that could be run. The idea of the universal machine was foreign to the world of Even ten years later, in , the big chief of the electromagnetic relay calculator at Harvard, Howard Aiken, could write: If it should turn out that the basic logics of a machine designed for the numerical solution of differential equations coincide with the logics of a machine intended to make bills for a department store, I would regard this as the most amazing coincidence that I have ever encountered.
But that is exactly how it has turned out. It is amazing, although we now have come to take it for granted. But it follows from the deep principle that Alan Turing saw in Of course, there have always been lousy predictions about computers. I follow the second viewpoint: Turing himself referred to computers in the modern sense as 'Practical Universal Computing Machines'. This Scrapbook page has emphasised the importance of Turing's logical theory of the Universal Machine, and its implementation as the computer with internally stored program.
But there is more to Turing's claim than this. What is a Computer? The machine you are looking at. The world's computer industries now make billions out of manufacturing better and better versions of Turing's universal machine.
Charles Babbage, and Ada Lovelace, Wikipedia: Charles Babbage and Ada Lovelace. Ada Lovelace's descriptive notes on the Analytical Engine, including an algorithm for calculating Bernoulli numbers.
More on near-computers ENIAC Even when they turned to electronics, builders of calculators still thought of programs as something quite different from numbers, and stored them in quite a different, inflexible, way. Colossus The Colossus was also started in at Bletchley Park, heart of the British attack on German ciphers see this Scrapbook page. Zuse's machines Konrad Zuse, in Germany, quite independently designed mechanical and electromechanical calculators, before and during the war.
He didn't use electronics. He still had a program on a paper tape: Konrad Zuse, , with the Z3. There are very artificial ways in which the pre-computers Babbage, Zuse, Colossus can be configured so as to mimic the operation of a computer in the modern sense. That is, it can be argued that they are potentially 'Turing-complete'. Alan Turing, on the basis of his own logical theory, and his knowledge of the power of electronic digital technology. John von Neumann, John von Neumann originally Hungarian was a major twentieth-century mathematician with work in many fields unrelated to computers.
So who invented the computer? There are many different views on which aspects of the modern computer are the most central or critical. Some people think that it's the idea of using electronics for calculating — in which case another American pioneer, Atanasoff, should be credited.
Other people say it's getting a computer actually built and working. From Theory to Practice: Alan Turing's ACE This Scrapbook page has emphasised the importance of Turing's logical theory of the Universal Machine, and its implementation as the computer with internally stored program. He designed his own computer in full detail as soon as the Second World War was over. Continue to the next Scrapbook page.More...