THE FIRST COMPUTER

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1、Who invented the computer and how?Who Invented The First Computer?Posted In: Household Items. Bookmark and Share When you ask the question stated above, you definitely need to be prepared to hear many different answers. There is not one simple answer to the question because there have been many type

2、s of computers (or computing machines) dating back to the 1800s.Charles Babbage, inventor of the first mechanical computerCharles Babbage is credited as the inventor of the first mechanical computer.The first, programmable “computing machine”Without getting too technical, the first “computing machin

3、e” was created by Charles Babbage in 1822. His idea was not really to create a computer as we know them today, but instead, to create a machine that would compute math problems. He was tired of human errors in completing math problems, so he sought to create an infallible math machine, but what he g

4、ot instead was a machine that was the basis for what we know now as the computer.BirthplaceCharles Babbage was born in England, and spent his life and career there. England is proud of its son, and some of his works are displayed at a museum in London. Charles attended Trinity College at Cambridge U

5、niversity, and completed his studies at Peterhouse Cambridge in mathematics. This education would help to guide him to his lifes most important work.The Babbage machineCharles Babbages machine, the Babbage machine was the first programmable, analytical machine and it was a fully automatic calculatin

6、g machine. Fundamentally, modern day computers do the same thing, read a program and execute it.It was programmableThe unique thing about Babbages machine was that you could program it. Previous invention of the calculator was already available but worked on a fixed sets of rules.Invention of the co

7、mputerIsnt it amazing that the invention Babbage sought to create ended up being something that would benefit human life centuries later? Babbage used the knowledge he gained through his education to work on a machine that would figure out math problems. Unfortunately, he never got to see the full c

8、ompletion of his dream project because he ran out of money. Although his machine was left uncompleted, his idea was later developed into a version of the computer that we know of today, and Babbage is generally considered the “father of computers”.Charles Babbages machine, the Babbage machine was th

9、e first programmable, analytical machine and it was a fully automatic calculating machine. Fundamentally, modern day computers do the same thing, read a program and execute it.We could argue that the first computer was the abacus or its descendant, the slide rule, invented by William Oughtred in 162

10、2. But the first computer resembling todays modern machines was the Analytical Engine, a device conceived and designed by British mathematician Charles Babbage between 1833 and 1871. Before Babbage came along, a computer was a person, someone who literally sat around all day, adding and subtracting

11、numbers and entering the results into tables. The tables then appeared in books, so other people could use them to complete tasks, such as launching artillery shells accurately or calculating taxes.It was, in fact, a mammoth number-crunching project that inspired Babbage in the first place source: C

12、ampbell-Kelly. Napoleon Bonaparte initiated the project in 1790, when he ordered a switch from the old imperial system of measurements to the new metric system. For 10 years, scores of human computers made the necessary conversions and completed the tables. Bonaparte was never able to publish the ta

13、bles, however, and they sat collecting dust in the Acadmie des sciences in Paris.In 1819, Babbage visited the City of Light and viewed the unpublished manuscript with page after page of tables. If only, he wondered, there was a way to produce such tables faster, with less manpower and fewer mistakes

14、. He thought of the many marvels generated by the Industrial Revolution. If creative and hardworking inventors could develop the cotton gin and the steam locomotive, then why not a machine to make calculations source: Campbell-Kelly?Babbage returned to England and decided to build just such a machin

15、e. His first vision was something he dubbed the Difference Engine, which worked on the principle of finite differences, or making complex mathematical calculations by repeated addition without using multiplication or division. He secured government funding in 1824 and spent eight years perfecting hi

16、s idea. In 1832, he produced a functioning prototype of his table-making machine, only to find his funding had run out.But, as you might have guessed, the story doesnt end there.Charles Babbage and the Analytical EngineSome people might have been discouraged, but not Babbage. Instead of simplifying

17、his design to make the Difference Engine easier to build, he turned his attention to an even grander idea - the Analytical Engine, a new kind of mechanical computer that could make even more complex calculations, including multiplication and division.The basic parts of the Analytical Engine resemble

18、 the components of any computer sold on the market today. It featured two hallmarks of any modern machine: a central processing unit, or CPU, and memory. Babbage, of course, didnt use those terms. He called the CPU the mill. Memory was known as the store. He also had a device - the reader - to input

19、 instructions, as well as a way to record, on paper, results generated by the machine. Babbage called this output device a printer, the precursor of inkjet and laser printers so common today.Babbages new invention existed almost entirely on paper. He kept voluminous notes and sketches about his comp

20、uters - nearly 5,000 pages worth - and although he never built a single production model of the Analytical Engine, he had a clear vision about how the machine would look and work. Borrowing the same technology used by the Jacquard loom, a weaving machine developed in 1804-05 that made it possible to

21、 create a variety of cloth patterns automatically, data would be entered on punched cards. Up to 1,000 50-digit numbers could be held in the computers store. Punched cards would also carry the instructions, which the machine could execute out of sequential order. A single attendant would oversee the

22、 whole operation, but steam would power it, turning cranks, moving cams and rods, and spinning gearwheels.Unfortunately, the technology of the day couldnt deliver on Babbages ambitious design. It wasnt until 1991 that his particular ideas were finally translated into a functioning computer. Thats wh

23、en the Science Museum in London built, to Babbages exact specifications, his Difference Engine. It stands 11 feet long and 7 feet tall (more than 3 meters long and 2 meters tall), contains 8,000 moving parts and weighs 15 tons (13.6 metric tons). A copy of the machine was built and shipped to the Co

24、mputer History Museum in Mountain View, Calif., where it remained on display until December 2010. Neither device would function on a desktop, but they are no doubt the first computers and precursors to the modern PC.First general-purpose computing deviceA portion of Babbages Difference engine.Charle

25、s Babbage, an English mechanical engineer and polymath, originated the concept of a programmable computer. Considered the father of the computer,4 he conceptualized and invented the first mechanical computer in the early 19th century. After working on his revolutionary difference engine, designed to

26、 aid in navigational calculations, in 1833 he realized that a much more general design, an Analytical Engine, was possible. The input of programs and data was to be provided to the machine via punched cards, a method being used at the time to direct mechanical looms such as the Jacquard loom. For ou

27、tput, the machine would have a printer, a curve plotter and a bell. The machine would also be able to punch numbers onto cards to be read in later. The Engine incorporated an arithmetic logic unit, control flow in the form of conditional branching and loops, and integrated memory, making it the firs

28、t design for a general-purpose computer that could be described in modern terms as Turing-complete.The machine was about a century ahead of its time. All the parts for his machine had to be made by hand - this was a major problem for a device with thousands of parts. Eventually, the project was diss

29、olved with the decision of the British Government to cease funding. Babbages failure to complete the analytical engine can be chiefly attributed to difficulties not only of politics and financing, but also to his desire to develop an increasingly sophisticated computer and to move ahead faster than

30、anyone else could follow. Nevertheless his son, Henry Babbage, completed a simplified version of the analytical engines computing unit (the mill) in 1888. He gave a successful demonstration of its use in computing tables in 1906.Early analog computersSir William Thomsons third tide-predicting machin

31、e design, 187981During the first half of the 20th century, many scientific computing needs were met by increasingly sophisticated analog computers, which used a direct mechanical or electrical model of the problem as a basis for computation. However, these were not programmable and generally lacked

32、the versatility and accuracy of modern digital computers.7The first modern analog computer was a tide-predicting machine, invented by Sir William Thomson in 1872. The differential analyser, a mechanical analog computer designed to solve differential equations by integration using wheel-and-disc mech

33、anisms, was conceptualized in 1876 by James Thomson, the brother of the more famous Lord Kelvin.8The art of mechanical analog computing reached its zenith with the differential analyzer, built by H. L. Hazen and Vannevar Bush at MIT starting in 1927. This built on the mechanical integrators of James

34、 Thomson and the torque amplifiers invented by H. W. Nieman. A dozen of these devices were built before their obsolescence became obvious.The modern computer age beginsThe principle of the modern computer was first described by computer scientist Alan Turing, who set out the idea in his seminal 1936

35、 paper,9 On Computable Numbers. Turing reformulated Kurt Gdels 1931 results on the limits of proof and computation, replacing Gdels universal arithmetic-based formal language with the formal and simple hypothetical devices that became known as Turing machines. He proved that some such machine would

36、be capable of performing any conceivable mathematical computation if it were representable as an algorithm. He went on to prove that there was no solution to the Entscheidungsproblem by first showing that the halting problem for Turing machines is undecidable: in general, it is not possible to decid

37、e algorithmically whether a given Turing machine will ever halt.He also introduced the notion of a Universal Machine (now known as a Universal Turing machine), with the idea that such a machine could perform the tasks of any other machine, or in other words, it is provably capable of computing anyth

38、ing that is computable by executing a program stored on tape, allowing the machine to be programmable. Von Neumann acknowledged that the central concept of the modern computer was due to this paper.10 Turing machines are to this day a central object of study in theory of computation. Except for the

39、limitations imposed by their finite memory stores, modern computers are said to be Turing-complete, which is to say, they have algorithm execution capability equivalent to a universal Turing machine.The first electromechanical computersReplica of Zuses Z3, the first fully automatic, digital (electro

40、mechanical) computer.Early digital computers were electromechanical; electric switches drove mechanical relays to perform the calculation. These devices had a low operating speed and were eventually superseded by much faster all-electric computers, originally using vacuum tubes. The Z2, created by G

41、erman engineer Konrad Zuse in 1939, was one of the earliest examples of an electromechanical relay computer.11In 1941, Zuse followed his earlier machine up with the Z3, the worlds first working electromechanical programmable, fully automatic digital computer.1213 The Z3 was built with 2000 relays, i

42、mplementing a 22 bit word length that operated at a clock frequency of about 510 Hz.14 Program code and data were stored on punched film. It was quite similar to modern machines in some respects, pioneering numerous advances such as floating point numbers. Replacement of the hard-to-implement decima

43、l system (used in Charles Babbages earlier design) by the simpler binary system meant that Zuses machines were easier to build and potentially more reliable, given the technologies available at that time.15 The Z3 was probably a complete Turing machine.The introduction of electronic programmable com

44、puters with vacuum tubesPurely electronic circuit elements soon replaced their mechanical and electromechanical equivalents, at the same time that digital calculation replaced analog. The engineer Tommy Flowers, working at the Post Office Research Station in London in the 1930s, began to explore the

45、 possible use of electronics for the telephone exchange. Experimental equipment that he built in 1934 went into operation 5 years later, converting a portion of the telephone exchange network into an electronic data processing system, using thousands of vacuum tubes.7 In the US, John Vincent Atanaso

46、ff and Clifford E. Berry of Iowa State University developed and tested the AtanasoffBerry Computer (ABC) in 1942,16 the first automatic electronic digital computer.17 This design was also all-electronic and used about 300 vacuum tubes, with capacitors fixed in a mechanically rotating drum for memory

47、.18Colossus was the first electronic digital programmable computing device, and was used to break German ciphers during World War II.During World War II, the British at Bletchley Park achieved a number of successes at breaking encrypted German military communications. The German encryption machine,

48、Enigma, was first attacked with the help of the electro-mechanical bombes. To crack the more sophisticated German Lorenz SZ 40/42 machine, used for high-level Army communications, Max Newman and his colleagues commissioned Flowers to build the Colossus.18 He spent eleven months from early February 1

49、943 designing and building the first Colossus.19 After a functional test in December 1943, Colossus was shipped to Bletchley Park, where it was delivered on 18 January 194420 and attacked its first message on 5 February.Colossus was the worlds first electronic digital programmable computer.7 It used

50、 a large number of valves (vacuum tubes). It had paper-tape input and was capable of being configured to perform a variety of boolean logical operations on its data, but it was not Turing-complete. Nine Mk II Colossi were built (The Mk I was converted to a Mk II making ten machines in total). Coloss

51、us Mark I contained 1500 thermionic valves (tubes), but Mark II with 2400 valves, was both 5 times faster and simpler to operate than Mark 1, greatly speeding the decoding process.2122ENIAC was the first Turing-complete device,and performed ballistics trajectory calculations for the United States Ar

52、my.The US-built ENIAC23 (Electronic Numerical Integrator and Computer) was the first electronic programmable computer built in the US. Although the ENIAC was similar to the Colossus it was much faster and more flexible. It was unambiguously a Turing-complete device and could compute any problem that

53、 would fit into its memory. Like the Colossus, a program on the ENIAC was defined by the states of its patch cables and switches, a far cry from the stored program electronic machines that came later. Once a program was written, it had to be mechanically set into the machine with manual resetting of

54、 plugs and switches.It combined the high speed of electronics with the ability to be programmed for many complex problems. It could add or subtract 5000 times a second, a thousand times faster than any other machine. It also had modules to multiply, divide, and square root. High speed memory was lim

55、ited to 20 words (about 80 bytes). Built under the direction of John Mauchly and J. Presper Eckert at the University of Pennsylvania, ENIACs development and construction lasted from 1943 to full operation at the end of 1945. The machine was huge, weighing 30 tons, using 200 kilowatts of electric pow

56、er and contained over 18,000 vacuum tubes, 1,500 relays, and hundreds of thousands of resistors, capacitors, and inductors.Stored program computers eliminate the need for re-wiringA section of the Manchester Small-Scale Experimental Machine, the first stored-program computer.Early computing machines

57、 had fixed programs. Changing its function required the re-wiring and re-structuring of the machine.18 With the proposal of the stored-program computer this changed. A stored-program computer includes by design an instruction set and can store in memory a set of instructions (a program) that details

58、 the computation. The theoretical basis for the stored-program computer was laid by Alan Turing in his 1936 paper. In 1945 Turing joined the National Physical Laboratory and began work on developing an electronic stored-program digital computer. His 1945 report Proposed Electronic Calculator was the

59、 first specification for such a device. John von Neumann at the University of Pennsylvania, also circulated his First Draft of a Report on the EDVAC in 1945.7Ferranti Mark 1, c. 1951.The Manchester Small-Scale Experimental Machine, nicknamed Baby, was the worlds first stored-program computer. It was

60、 built at the Victoria University of Manchester by Frederic C. Williams, Tom Kilburn and Geoff Tootill, and ran its first program on 21 June 1948.25 It was designed as a testbed for the Williams tube the first random-access digital storage device.26 Although the computer was considered small and pri

61、mitive by the standards of its time, it was the first working machine to contain all of the elements essential to a modern electronic computer.27 As soon as the SSEM had demonstrated the feasibility of its design, a project was initiated at the university to develop it into a more usable computer, t

62、he Manchester Mark 1.The Mark 1 in turn quickly became the prototype for the Ferranti Mark 1, the worlds first commercially available general-purpose computer.28 Built by Ferranti, it was delivered to the University of Manchester in February 1951. At least seven of these later machines were delivere

63、d between 1953 and 1957, one of them to Shell labs in Amsterdam.29 In October 1947, the directors of British catering company J. Lyons & Company decided to take an active role in promoting the commercial development of computers. The LEO I computer became operational in April 1951 30 and ran the wor

64、lds first regular routine office computer job.Transistors replace vacuum tubes in computersA bipolar junction transistorThe bipolar transistor was invented in 1947. From 1955 onwards transistors replaced vacuum tubes in computer designs, giving rise to the second generation of computers. Compared to

65、 vacuum tubes, transistors have many advantages: they are smaller, and require less power than vacuum tubes, so give off less heat. Silicon junction transistors were much more reliable than vacuum tubes and had longer, indefinite, service life. Transistorized computers could contain tens of thousands of binary logic circuits in a relatively compact space.At the University of Manchester, a team under the leadership of Tom Kilburn designed and built a machine using the newly develop