The History of the Digital Computer

British? No, you're inventing it

British inventors have dreamed up dozens of things we now take for granted - but most of their countrymen don't appreciate their brilliance. That is the finding of a poll on what  people know about our scientific achievments. Three-quarters did not realise cloning and jet engines began in Britains, only a few more knew DNA and computers were pioneered here and half did not realise a Briton built the first steam engine. The London Science Museum,which held the poll, said the level of ignorance was "staggering".[Metro]

Alan TuringThe modern PC is the result of many stages of development in computing. In theory we could go all the way back to devices like the Abacus,but in more recent times,the concept of  programming a universal machine was initially started by Charles Babbage who made a computing engine from mechanical parts.
Subsequently,the mathematical foundation of what we now know as a computer was laid down by Alan Matheson Turing at Manchester University. Alan was a critical aid during the cracking of the ENIGMA code during WW2,it was his ideas of using a universal computing device which broke the German Cipher Codes.
His work has led to theoretical ideas about how the brain works and to the pursuit of artificial intelligence in modern robots. Alan also pioneered the 'Turing Test" which he devised to determine the difference between a human being and a machine - if a machine could fabricate the same responses,such that a human operator was unable to determine the difference between the responses a human might make and those of the machine,then he said we would have to say that the machine was artificially intelligent.

Mill Technology
Some of the concepts inside a computer are actually based on old mill technologies -and so you will find in procesors of yore that they had parts called "The Mill" - it is as well to understand that after the Industrial Revolution, moves to automate things gathered pace and whilst it may seem that a computer is a foreign and hard to understand device many of the ideas behind it started in the Mills which contained looms -in particular the Jacquard loom which used paper tape with holes in to 'program' a pattern into a piece of material was one of the concepts borrowed when some of the first computers were made. You will find that very old computers used 'punched tape' and 'punched card' systems to program them - which was a laborious task - and one mistake in the punching of the paper tape or card could lead to compound errors in the results.

Valve Technology
The earliest computers filled whole rooms with vacuum tubes and were 'valve technology' devices.Valves were prone to overheating and were basically untrustworthy,neverthless Alan Turing used such a machine to crack the ENIGMA code.

Transistor Technology
Later machines were 'transistor technology' devices.These were much smaller,but were still unreliable and prone to failure.

Microchip Technology
With the advent of the silicon chip,computer became much more reliable.Circuits etched onto a crystal of silicon at a microscopic level could process millions of instructions per second. The first computers entered the home market and were called "8 bit microcomputers" because computers use arithmetic based on 2,not upon 10 and 8 of the binary digits or 'bits' made up one letter of computer language. These computers could only have one program in memory at a time and their operating system was held in ROM,which meant as soon as you switched the computer on - it was ready to run. Subsequently,processors have handled longer and longer words and used faster and faster processors.

VLSI and parallel Technology
As many more transistors were etched onto a silicon chip VLSI chips (Very Large Scale Integration) were used. These days, the processors you will find inside a PC may harbour millions of individual components. Modern computers can run many programs simultaneously using "Windows",but their operating system is "soft" - that is - it has to be installed from some sort of media,usually CD-rom,and then it may take a while to "boot up" and start the operating system. This renders the computer more flexible,in that it needn't use the operating system supplied with it,but it takes longer before you can do anything with the computer.
Computers are also being made with more than one processor (CPU) and all of them work together collectively to achieve the end result - this is called 'working in parallel'.

GOOD GRID: The first map of the worlds most powerful computer grids is to be unveiled this week. Nine of the largest grids are featured in the display at the supercomputing festival in Tampa Florida. The map uses Google Earth to pinpoint more than 300 sites on six continents. Grids are made up of hundreds or thousands of PCs linked together to create a supercomputer. They are vital for scientists who need extra computing power to process large amounts of data.[Metro Minicosm Nov16,2006].

Supercomputers and AI
Supercomputers,such as those that predict the weather sometimes have to be water cooled or use special liquids to take the heat away from the processors. Inside your PC,the same process is carried out by fans,because the CPU is working so fast that,much like a car engine,it needs to be kept cool. One of the problems for supercomputers is how to get rid of this heat,you might like to compare what is going on with how your own brain manages to do the same job. Robots are beginning to take humanoid shape and as computing systems get more complex ,the possibility that they maybe able to think comes into sight. Many people think it is an impossibility and that perhaps their own belief systems are called into question should a machine achieve consciousness.
Other's believe a machine with no soul would be a Frankensteinian creation - Science fiction writer Isaac Asimov created his 3 rules of robotics in order that machines would not be able to harm humans

The Future
In the future computers may well take advantage of Quantum Physics and the first Quantum Computer is already on the horizon.Such machines use the QBIT rather than the bit. A bit can be either a 1 or a 0 - a Qbit takes on a 'superposed' state that can be both 1 and 0 at the same time,the curious physics which allows this may well be the same physics that your own brain uses,and so it maybe that such machines will be able to think like a human being.

Supercomputers 'to fit in palm of hand'

TINY supercomputers that fit into the palm of the hand could hit the shops in about a decade after groundbreaking research, it was claimed yesterday. The gadgets look set to be made using wires 1,000 times thinner than a human hair, said a team at Edinburgh University. The biggest problem was the discovery that wires measured in millionths of a millimetre take on 'very weird shapes' when attempts are made to bend them. Researchers led by Dr Michael Zaiser overcame this problem by creating a computer programme that predicts when this problem is going to happen, allowing engineers to avoid it. Dr Zaiser said: 'Holding a supercomputer in the palm of your hand will one day be possible and we are going to make sure all the wires are in the right place.' The next step is to make microchips much smaller than existing ones.
[Metro 22 Oct,2007]

See Also: The Computer ,Computers,Find Out More: The Computer,How it Works: The Computer,The History of the Digital Computer, Turing Archive, Alan Turing Biog,Parallel Power,Certainty from Uncertainty,Artificial Intelligence,AI