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History of computing hardware – Wikipedia
The history of computing hardware covers the developments from early simple devices to a calculation to modern day computers. Before the 20th century, …
Source: en.wikipedia.org
Date Published: 5/29/2022
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Linux Mint: Home
Linux Mint is an elegant, easy to use, up to date and comfortable desktop operating system. … Browse the Web, watch Youtube and Netflix with Firefox.
Source: linuxmint.com
Date Published: 10/8/2021
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What is Data? – Definition from WhatIs.com – TechTarget
Over the history of corporate computing, specialization occurred, and a distinct data profession emerged along with growth of corporate data processing. How …
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Date Published: 2/24/2021
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* Read the following passage and mark the letter A, B, C, or D …
THE DIGITAL DIVIDE Information technology is influencing the way many of us … Access to computers and the Internet will be important in …
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Date Published: 5/7/2021
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Headphone Jack Not Working On Laptop [SOLVED]
Don’t worry – it’s often quite easy to fix. … Here’s how: … chat, browse the internet, write documents, do school presentations, …
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Date Published: 11/18/2021
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History of computing hardware
From early calculation aids to modern computers
Parts of four early computers, 1962. Left to right: ENIAC board, EDVAC board, ORDVAC board, and BRLESC-I board, showing the trend toward miniaturization
The history of computer hardware includes the developments from early simple computing devices to modern computers. Before the 20th century, most calculations were done by humans.
The first calculation aids were purely mechanical devices that required the operator to set the initial values of an elementary arithmetic operation and then manipulate the device to obtain the result. Later, computers presented numbers in continuous form (e.g. distance along a scale, rotation of a shaft, or a voltage). Numbers could also be represented in the form of digits that are automatically manipulated by some mechanism. Although this approach generally required more complex mechanisms, it significantly increased the accuracy of the results. The development of transistor technology and then the integrated circuit chip led to a series of breakthroughs, beginning with transistor computers and then integrated circuit computers, leading to digital computers largely replacing analog computers. Metal-oxide-semiconductor (MOS) large-scale integration (LSI) then enabled semiconductor memory and the microprocessor, leading to another major breakthrough in the 1970s, the miniaturized personal computer (PC). The cost of computers gradually got so low that personal computers became ubiquitous in the 1990s and then mobile computers (smartphones and tablets) in the 2000s.
Early devices[ edit ]
Antiquity and the Middle Ages[edit]
Suanpan (the number represented on this abacus is 6,302,715,408)
Devices have been used to aid in calculations for thousands of years, primarily using one-to-one correspondence with the fingers. The earliest counting device was probably some kind of tally sheet. The Lebombo bone from the mountains between Eswatini and South Africa is possibly the oldest known mathematical artifact.[2] It dates back to 35,000 BC. It consists of 29 different notches intentionally cut into a baboon’s fibula. Later recording aids throughout the Fertile Crescent included calculi (clay balls, cones, etc.) representing counts of objects, probably cattle or grain, sealed in hollow, unbaked clay containers. [b][6][c] The use of counting rods is an example. The abacus was used early on for arithmetic. What we now call the Roman abacus was in use in Babylonia as early as c. 2700-2300 BC Since then, many other forms of arithmetic tables or charts have been invented. In a medieval European trading office, a checkered cloth was placed on a table on which markers were moved according to certain rules to calculate sums of money.
In ancient and medieval times, several analog computers were constructed to perform astronomical calculations. These included the astrolabe and the Antikythera mechanism from the Hellenistic world (ca. 150–100 BC).[8] In Roman Egypt, the Hero of Alexandria (c. AD 10–70) made mechanical devices, including automata and a programmable cart.[9] Other early mechanical devices used to perform one type of calculation or another include the planisphere and other mechanical calculating devices invented by Abu Rayhan al-Biruni (c. AD 1000); the equator and universal latitude-independent astrolabe of Abu Ishāq Ibrāhīm al-Zarqālī (c. AD 1015); the astronomical analog computers of other medieval Muslim astronomers and engineers; and the Su Song Astronomical Bell Tower (1094) during the Song Dynasty. The Castle Clock, a hydro-powered mechanical astronomical clock invented by Ismail al-Jazari in 1206, was the first programmable analog computer. [10][11][12] Ramon Llull invented the Lullian Circle: a fictional machine for computing answers to philosophical questions (in this case about Christianity) via logical combinatorics. This idea was taken up by Leibniz centuries later and is therefore one of the founding elements of computer science and information science.
Scottish mathematician and physicist John Napier discovered that numbers can be multiplied and divided by adding or subtracting the logarithms of those numbers. In creating the first logarithmic tables, Napier had to perform many tedious multiplications. It was at this point that he designed his “Napier bones,” an abacus-like device that greatly simplified calculations involving multiplication and division.[d]
A modern slide rule
Because real numbers can be represented as distances or intervals on a line, the slide rule was invented in the 1620s, shortly after Napier’s work, to perform multiplication and division operations much faster than previously possible.[13] Edmund Gunter built a calculator with a single logarithmic scale at Oxford University. His device greatly simplified arithmetic calculations, including multiplication and division. William Oughtred greatly improved this in 1630 with his circular slide rule. This was followed in 1632 by the modern slide rule, essentially a combination of two Gunter rules held together with the hands. Slide rules were used by generations of engineers and other mathematical professionals up until the invention of the pocket calculator.[14]
Mechanical calculators[edit]
Wilhelm Schickard, a German polymath, designed a calculating machine in 1623 that combined a mechanized form of Napier sticks with the world’s first mechanical adding machine built into the base. Because it used a single gear, there were circumstances where its support mechanism would jam.[15] A fire destroyed at least one of the machines in 1624 and it is believed that Schickard was too discouraged to build another.
In 1642, while still a teenager, Blaise Pascal pioneered calculating machines and after three years of effort and 50 prototypes[16] invented a mechanical calculator.[17][18] Over the next ten years he built twenty of these machines (called Pascal’s calculators or Pascalines).[19] Nine pascalines have survived, most of which are on display in European museums.[20] Whether Schickard or Pascal should be considered the “inventors of mechanical arithmetic” is a matter of ongoing debate, and the range of issues to be considered is discussed elsewhere.[21]
A set of abacus by John Napier from around 1680
Gottfried Wilhelm von Leibniz invented the step calculator and his famous step drum mechanism around 1672. He was trying to create a machine that could not only be used for adding and subtracting, but would use a moving carriage to allow for long multiplications and divisions. Leibniz once said, “It is unworthy of an excellent man to waste hours like slaves in arithmetic work that could safely be left to someone else if machines were used.” [22] However, Leibniz did not incorporate a fully successful carrying mechanism. Leibniz also described the binary number system,[23] a central component of all modern computers. However, up until the 1940s many subsequent designs (including Charles Babbage’s 1822 machines and even 1945 ENIAC) were based on the decimal system.
Detail of an arithmometer built before 1851. The single digit multiplier cursor (ivory on top) is the leftmost cursor
Around 1820, Charles Xavier Thomas de Colmar created what would become the first successful mass-produced mechanical calculator later in the century, the Thomas Arithmometer. It could be used for addition and subtraction, and with a moving carriage the operator could also multiply and divide using a process of long multiplication and long division.[24] It used a graduated drum similar to that invented by Leibniz. Mechanical calculators remained in use until the 1970s.
Punch card data processing[ edit ]
In 1804, the French weaver Joseph Marie Jacquard developed a loom in which the pattern to be woven was controlled by a paper tape made from punched cards. The paper tape could be changed without changing the mechanical design of the loom. This was a milestone in programmability. His machine was an improvement over similar looms. Punched cards were preceded by punched tape, as in the machine proposed by Basile Bouchon. These tapes would inspire information recording for automatic pianos and, more recently, numerically controlled machine tools.
At the end of the 1880s, the American Herman Hollerith invented data storage on punched cards, which could then be read by a machine.[25] To process these punched cards, he invented the tabulator and the punching machine. His machines used electromechanical relays and counters.[26] Hollerith’s method was used in the 1890 United States Census. This census was processed two years faster than the previous census.[27] Hollerith’s company eventually became the core of IBM.
By 1920, electromechanical tabulation machines could add, subtract, and print cumulative totals.[28] Machine functions were controlled by inserting dozens of jumper wires into detachable control panels. When the United States introduced Social Security in 1935, IBM punch card systems were used to process records from 26 million workers.[29] Punch cards became ubiquitous in industry and government for accounting and administration.
Leslie Comrie’s article on punch card methods and W. J. Eckert’s 1940 publication of Punched Card Methods in Scientific Computation described punch card techniques advanced enough to solve some differential equations[30] or to perform multiplication and division using floating point representations, all on punch cards and unit recording machines. Such machines were used for cryptographic statistical processing during World War II, as well as for a variety of administrative purposes. Columbia University’s Astronomical Computing Bureau performed astronomical calculations that represent the state of the art in computing.[31][32]
calculator [ edit ]
The Curta calculator could also do multiplication and division.
By the 20th century, earlier mechanical calculators, cash registers, accounting machines, etc. were redesigned to use electric motors, with gear position serving as a representation of a variable’s state. The word “computer” was a job title attributed primarily to women who used these calculators to perform mathematical calculations.[33] In the 1920s, British scientist Lewis Fry Richardson’s interest in weather forecasting led him to propose human computers and numerical analysis to model the weather. to date, the most powerful computers on earth are required to adequately model the weather using the Navier-Stokes equations.[34]
From the 1930s, companies such as Friden, Marchant Calculator, and Monroe manufactured mechanical desktop calculators that could add, subtract, multiply, and divide.[35] In 1948 the Curta was introduced by the Austrian inventor Curt Herzstark. It was a small, hand-cranked mechanical calculating machine and as such was a descendant of Gottfried Leibniz’ Stepped Reckoner and Thomas’ Arithmometer.
The world’s first fully electronic desktop calculator was the British Bell Punch ANITA, which came onto the market in 1961.[36][37] It used vacuum tubes, cold-cathode tubes, and dekatrons in its circuitry, with 12 cold-cathode “Nixie” tubes for its display. The ANITA sold well because it was the only electronic desktop calculator available and because it was quiet and fast. Tube technology was superseded in June 1963 by the US-made Friden EC-130, which had an all-transistor design, a stack of four 13-digit numbers on a 5-inch (13 cm) CRT, and reversed Polish notation (UPN) .
First general-purpose computing device[ edit ]
Charles Babbage, an English mechanical engineer and polymath, developed the concept of a programmable computer. He is considered the “father of the computer”[38] and designed and invented the first mechanical computer at the beginning of the 19th century. In 1833, after working on his revolutionary difference engine, designed to aid in navigational computations, he realized that a much more general design, an analytic engine, was possible. The input of programs and data was to be made available to the machine via punched cards, a method then used to control mechanical looms such as the Jacquard loom. For output, the machine would have a printer, a curve plotter and a bell. The machine could also punch numbers onto cards for later reading. It used ordinary fixed-point base 10 arithmetic.
The engine incorporated an arithmetic logic unit, control flow in the form of conditional branches and loops, and onboard memory, making it the first design for a general-purpose computer that could be called Turing-complete in modern terms. 40]
There should be a memory that could hold 1,000 numbers with 40 decimal places each (approx. 16.7 kB). An arithmetic unit called “Mill” would be able to perform all four arithmetic operations plus comparisons and optionally square roots. Originally it was conceived as another machine bent back on itself in a generally circular layout, with the long store exiting one side. (Later drawings show a regular grid layout.)[42] Like the central processing unit (CPU) in a modern computer, the mill would rely on its own internal procedures, roughly equivalent to the microcode in modern CPUs, to store in the form are used by pins that are inserted into rotating drums called “barrels” to carry out some of the more complex instructions that the user’s program might dictate.
Experimental model of part of the Analytical Engine built by Babbage on display at the Science Museum, London
The programming language to be used by the users was similar to modern assembly languages. Loops and conditional branches were possible, and so the language conceived would have been Turing-complete, as later defined by Alan Turing. Three different types of punch cards were used: one for arithmetic operations, one for numeric constants, and one for load and store operations, transferring numbers from memory to the arithmetic unit or back. There were three separate readers for the three types of cards.
The machine was about a century ahead of its time. However, the project was slowed by various issues, including disputes with the chief mechanic who was building parts for it. All of the parts for his machine had to be handcrafted—a major problem for a machine with thousands of parts. Eventually the project was wound up with the UK government’s decision to stop funding. Babbage’s failure to complete the Analytical Engine can be largely attributed not only to political and financial difficulties, but also to his desire to develop an ever more sophisticated computer and to advance faster than anyone else could follow. Ada Lovelace translated and annotated Luigi Federico Menabrea’s Sketch of the Analytical Engine. This appears to be the first published description of programming, hence Ada Lovelace is widely considered to be the first female computer programmer.[44]
Torres Quevedo’s 1920 electromechanical arithmometer, one of several designs based on Babbage. This prototype automatically performed arithmetic operations and used a typewriter to send commands and print out the results.
Babbage was succeeded by Percy Ludgate, a clerk at a corn trader in Dublin, Ireland, although he was initially unaware of his previous work. He independently designed a programmable mechanical computer, which he described in a paper published in 1909. Two other inventors, Leonardo Torres y Quevedo and Vannevar Bush, also followed research based on Babbage’s work. In his Essays on Automatics (1913), Torres y Quevedo designed a Babbage-type calculating machine using electromechanical parts containing floating-point number representations and built an early prototype in 1920. Bush’s article Instrumental Analysis (1936) discussed the use of existing IBM punch card machines to implement Babbage’s design. In the same year he started the Rapid Arithmetical Machine project to study the problems in building an electronic digital computer.[47]
Analog computers[ edit ]
In the first half of the 20th century, analog computers were seen by many as the future of computing. These devices used the ever-changing aspects of physical phenomena, such as electrical, mechanical, or hydraulic quantities, to model the problem to be solved, in contrast to digital computers, which symbolically represented varying quantities as their numerical values changed. Because an analog computer uses continuous values rather than discrete values, processes cannot be reliably repeated with exact equivalence as Turing machines can.[48]
The first modern analogue computer was a tide forecasting machine invented in 1872 by Sir William Thomson, later Lord Kelvin. She used a system of pulleys and wires to automatically calculate predicted tide levels for a specific period of time at a specific location, a great benefit for shallow-water navigation. His device was the basis for further developments in analogue computing.[49]
The differential analyzer, a mechanical analog computer designed to solve differential equations through integration with wheel-and-disc mechanisms, was conceived in 1876 by James Thomson, brother of the more famous Lord Kelvin. He explored the possible design of such calculators, but was hampered by the limited output torque of ball-disk integrators.[50] In a differential analyzer, the output of one integrator controlled the input of the next integrator, or a graphical output.
A Mk. I drive sight. The lever just in front of the bomb aimer’s fingertips adjusts the altitude, the wheels near his knuckles adjust the wind and airspeed.
A major advance in analog computing was the development of the first fire control systems for long-range gunnery. As firing ranges increased dramatically in the late 19th century, given the shells’ flight times, it was no longer simply a matter of calculating the correct point of aim. Various spotters on board the ship would relay distance measurements and observations to a central plotter station. There, the fire control teams entered the location, speed, and direction of the ship and its target, as well as various adjustments for the Coriolis effect, mid-air weather effects, and other adjustments. The computer would then issue a firing solution that would be fed to the turrets for laying. In 1912, British engineer Arthur Pollen developed the first electrically powered mechanical analog computer (then called the Argo clock). [citation needed] It was used by the Imperial Russian Navy in World War I. [citation needed] The alternative Dreyer table fire control system was installed on British capital ships in mid-1916.
Mechanical devices were also used to aid in the accuracy of aerial bombing raids. Drift Sight was the first such tool, developed in 1916 by Harry Wimperis for the Royal Naval Air Service. It measured the wind speed from the air and used this measurement to calculate the effects of the wind on the trajectory of the bombs. The system was later improved with the Course Setting Bomb Sight and peaked with WWII bomb sights, Mark XIV bomb sights (RAF Bomber Command) and the Norden[51] (United States Army Air Forces).
The art of mechanical analog computing reached its zenith with the differential analyzer[52] built by HL Hazen and Vannevar Bush at MIT beginning in 1927 and based on the mechanical integrators of James Thomson and the torque amplifiers invented by HW Nieman. A dozen of these devices were built before their obsolescence became apparent; The most powerful was built at the University of Pennsylvania’s Moore School of Electrical Engineering, where the ENIAC was built.
A fully electronic analog computer was built in 1942 by Helmut Holzer in the Peenemünde Army Research Institute.[53][54][55]
By the 1950s, the success of digital electronic computers had spelled the end of most analog calculators, but hybrid analog computers controlled by digital electronics remained in widespread use in some specialty applications through the 1950s and 1960s and later.
Advent of the digital computer[edit]
The principle behind the modern computer was first described by computer scientist Alan Turing, who laid out the idea in his seminal 1936 paper On Computable Numbers[56]. Turing restated Kurt Gödel’s 1931 results on the limits of proofs and computations, and replaced Gödel’s universal, arithmetic-based formal language with the formal and simple hypothetical devices that became known as Turing machines. He proved that such a machine would be able to perform any mathematical calculation imaginable if it could be represented as an algorithm. He further proved that there is no solution to the decision problem by first showing that the halting problem is undecidable for Turing machines: in general, it is not possible to decide 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 was demonstrably capable of anything to calculate is calculable by running a program stored on tape, making the machine programmable. Von Neumann acknowledged that the central concept of the modern computer came from this work.[57] Turing machines are still a central object of investigation in the theory of computing. Apart from the limitations imposed by their finite memories, modern computers are considered Turing-complete, i.e. H. they have the ability to run algorithms equivalent to a universal Turing machine.
Electromechanical computers[edit]
The era of modern computers began with rapid development before and during World War II. Most digital computers built during this period were electromechanical – electrical switches drove mechanical relays to perform the calculation. These devices had slow operating speeds and were eventually replaced by much faster all-electric computers that originally used vacuum tubes.
The Z2 was one of the earliest examples of an electromechanical relay computer and was developed in 1940 by German engineer Konrad Zuse. It was an improvement on his earlier Z1; Although it used the same mechanical memory, it replaced the arithmetic and control logic with electrical relay circuits.
Replica of Zuse’s Z3, the first fully automatic, digital (electromechanical) computer
In the same year, electromechanical devices called bombs were built by British cryptologists to decrypt secret messages encrypted with the German Enigma machine during World War II. The original design of the bomb was created by Alan Turing at the UK Government Code and Cypher School (GC&CS) at Bletchley Park in 1939,[59] with an important refinement being developed by Gordon Welchman in 1940.[60] The technical design and construction was the work of Harold Keen of the British Tabulating Machine Company. It was a major advancement of a device designed in 1938 by the Polish Cipher Bureau cryptologist Marian Rejewski, known as the “cryptological bomb” (Polish: “bomba kryptologiczna”).
In 1941, Zuse followed his earlier machine with the Z3,[58] the world’s first functioning electromechanically programmable, fully automatic digital computer.[61] The Z3 was built with 2000 relays and implemented a 22-bit word length operating at a clock frequency of about 5–10 Hz.[62] Program code and data were stored on perforated foil. It was quite similar to modern machines in some respects and pioneered numerous advances such as floating point numbers. The replacement of the difficult-to-implement decimal system (used in Charles Babbage’s earlier design) with the simpler binary system meant that given the technologies then available, Zuse’s machines were easier to build and potentially more reliable. The Z3 was proved to be a Turing complete machine by Raúl Rojas in 1998.[64] In two 1936 patent applications, Zuse also posited that machine instructions could be stored in the same memory used for data – the key finding of the so-called von Neumann architecture, first implemented in America in the electromechanical IBM SSEC in 1948 and in Britain in the fully electronic Manchester Baby.[65]
Zuse suffered setbacks in World War II when some of his machines were destroyed in Allied bombing raids. Apparently his work remained largely unknown to engineers in Britain and the US until much later, although IBM at least knew about it, as it funded its post-war start-up company in 1946 in exchange for an option on Zuse’s patents.
In 1944, the Harvard Mark I was constructed at IBM’s Endicott Laboratories.[66] It was a similar general-purpose electromechanical computer to the Z3, but not quite Turing-complete.
Digital computation[ edit ]
The term digital was first proposed by George Robert Stibitz and refers to a signal such as a voltage, is not used to represent a value directly (as would be the case in an analog computer) but to encode it. In November 1937, Stibitz, then working at Bell Labs (1930–1941), completed a relay-based calculator that he later called the “Model K” (for “kitchen table” on which he assembled it), which became the first binary adder. [68] Typically, signals have two states – low (usually representing 0) and high (usually representing 1), but three-valued logic is sometimes used, particularly in high-density memories. Modern computers generally use binary logic, but many early machines were decimal computers. In these machines, the basic unit of data was the decimal digit, encoded in one of several schemes including binary coded decimal or BCD, bi-quinary, excess-3, and two-of-five codes.
The mathematical basis of digital computing is Boolean algebra, developed by British mathematician George Boole in his The Laws of Thought, published in 1854. His Boolean algebra was further refined by William Jevons and Charles Sanders Peirce in the 1860s and first presented systematically by Ernst Schröder and A. N. Whitehead.[69] In 1879 Gottlob Frege developed the formal approach to logic and proposed the first logical language for logical equations.[70]
In the 1930s, American electronics engineer Claude Shannon and Soviet logician Victor Shestakov independently demonstrated a one-to-one correspondence between the concepts of Boolean logic and certain electrical circuits, now called logic gates, which are now ubiquitous in digital computers . [71] They showed[72] that electronic relays and switches can realize the expressions of Boolean algebra. This diploma thesis essentially established the practical digital circuit design. In addition, Shannon’s article gives a correct circuit diagram for a 4-bit digital binary adder.[71]: pp.494–495
Electronic data processing[ edit ]
Rein elektronische Schaltungselemente ersetzten bald ihre mechanischen und elektromechanischen Äquivalente, gleichzeitig ersetzte die digitale Berechnung die analoge. Maschinen wie der Z3, der Atanasoff-Berry-Computer, die Colossus-Computer und der ENIAC wurden von Hand gebaut, wobei Schaltkreise mit Relais oder Ventilen (Vakuumröhren) verwendet wurden und häufig Lochkarten oder Lochpapier für die Eingabe und als Haupt verwendet wurden (nichtflüchtiges) Speichermedium.[73]
Der Ingenieur Tommy Flowers trat 1926 in die Telekommunikationsabteilung des General Post Office ein. Während er in den 1930er Jahren an der Forschungsstation in Dollis Hill arbeitete, begann er, die mögliche Verwendung von Elektronik für die Telefonzentrale zu untersuchen. Eine Versuchsanlage, die er 1934 baute, ging 5 Jahre später in Betrieb und wandelte einen Teil des Telefonvermittlungsnetzes in ein elektronisches Datenverarbeitungssystem um, das Tausende von Vakuumröhren verwendete.[49]
In den USA erfand Arthur Dickinson (IBM) 1940 den ersten digitalen elektronischen Computer.[74] Dieses Rechengerät war vollelektronisch – Steuerung, Berechnung und Ausgabe (die erste elektronische Anzeige).[75] John Vincent Atanasoff und Clifford E. Berry von der Iowa State University entwickelten 1942 den Atanasoff-Berry-Computer (ABC),[76] das erste binäre elektronische digitale Rechengerät.[77] Dieses Design war halbelektronisch (elektromechanische Steuerung und elektronische Berechnungen) und verwendete etwa 300 Vakuumröhren mit Kondensatoren, die in einer mechanisch rotierenden Trommel als Speicher befestigt waren. Sein Papierkartenschreiber/-leser war jedoch unzuverlässig und das regenerative Trommelkontaktsystem war mechanisch. Die Spezialität der Maschine und das Fehlen eines veränderbaren, gespeicherten Programms unterscheiden sie von modernen Computern.
Computer, deren Logik hauptsächlich mit Vakuumröhren aufgebaut wurde, werden heute als Computer der ersten Generation bezeichnet.
Der elektronisch programmierbare Computer [ bearbeiten ]
Der digitale Koloss war das erste elektronische programmierbare Rechengerät und wurde verwendet, um deutsche Chiffren während des Zweiten Weltkriegs zu brechen. Es blieb als militärisches Geheimnis bis weit in die 1970er Jahre unbekannt
Während des Zweiten Weltkriegs erzielten britische Codeknacker in Bletchley Park, 40 Meilen (64 km) nördlich von London, eine Reihe von Erfolgen beim Knacken verschlüsselter feindlicher militärischer Kommunikation. Mit Hilfe der elektromechanischen Bomben wurde zunächst die deutsche Chiffriermaschine Enigma angegriffen.[79] Frauen bedienten diese Bombenmaschinen oft.[80][81] Sie schlossen mögliche Enigma-Einstellungen aus, indem sie elektrisch implementierte Ketten logischer Ableitungen durchführten. Die meisten Möglichkeiten führten zu einem Widerspruch, und die wenigen verbleibenden konnten von Hand getestet werden.
Die Deutschen entwickelten auch eine Reihe von Fernschreibverschlüsselungssystemen, ganz anders als Enigma. Die Lorenz SZ 40/42-Maschine wurde für hochrangige Armeekommunikation verwendet und von den Briten mit dem Codenamen “Tunny” bezeichnet. Das erste Abfangen von Lorenz-Nachrichten begann im Jahr 1941. Als Teil eines Angriffs auf Tunny entwickelten Max Newman und seine Kollegen den Heath Robinson, eine Maschine mit fester Funktion, um beim Codeknacken zu helfen. Tommy Flowers, ein leitender Ingenieur an der Post Office Research Station[83] wurde Max Newman von Alan Turing[84] empfohlen und verbrachte ab Anfang Februar 1943 elf Monate damit, den flexibleren Colossus-Computer zu entwerfen und zu bauen (der den Heath Robinson ablöste). [85][86] Nach einem Funktionstest im Dezember 1943 wurde Colossus nach Bletchley Park verschifft, wo es am 18. Januar 1944 ausgeliefert wurde[87] und seine erste Nachricht am 5. Februar angriff.
Kriegsfoto von Colossus No. 10
Colossus war der weltweit erste elektronisch digital programmierbare Computer.[49] Es verwendete eine große Anzahl von Ventilen (Vakuumröhren). It had paper-tape input and was capable of being configured to perform a variety of boolean logical operations on its data,[89] but it was not Turing-complete. Data input to Colossus was by photoelectric reading of a paper tape transcription of the enciphered intercepted message. This was arranged in a continuous loop so that it could be read and re-read multiple times – there being no internal store for the data. The reading mechanism ran at 5,000 characters per second with the paper tape moving at 40 ft/s (12.2 m/s; 27.3 mph). Colossus Mark 1 contained 1500 thermionic valves (tubes), but Mark 2 with 2400 valves and five processors in parallel, was both 5 times faster and simpler to operate than Mark 1, greatly speeding the decoding process. Mark 2 was designed while Mark 1 was being constructed. Allen Coombs took over leadership of the Colossus Mark 2 project when Tommy Flowers moved on to other projects.[90] The first Mark 2 Colossus became operational on 1 June 1944, just in time for the Allied Invasion of Normandy on D-Day.
Most of the use of Colossus was in determining the start positions of the Tunny rotors for a message, which was called “wheel setting”. Colossus included the first-ever use of shift registers and systolic arrays, enabling five simultaneous tests, each involving up to 100 Boolean calculations. This enabled five different possible start positions to be examined for one transit of the paper tape.[91] As well as wheel setting some later Colossi included mechanisms intended to help determine pin patterns known as “wheel breaking”. Both models were programmable using switches and plug panels in a way their predecessors had not been. Ten Mk 2 Colossi were operational by the end of the war.
Without the use of these machines, the Allies would have been deprived of the very valuable intelligence that was obtained from reading the vast quantity of enciphered high-level telegraphic messages between the German High Command (OKW) and their army commands throughout occupied Europe. Details of their existence, design, and use were kept secret well into the 1970s. Winston Churchill personally issued an order for their destruction into pieces no larger than a man’s hand, to keep secret that the British were capable of cracking Lorenz SZ cyphers (from German rotor stream cipher machines) during the oncoming Cold War. Two of the machines were transferred to the newly formed GCHQ and the others were destroyed. As a result, the machines were not included in many histories of computing.[f] A reconstructed working copy of one of the Colossus machines is now on display at Bletchley Park.
The US-built ENIAC (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 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 plugs and switches. The programmers of the ENIAC were women who had been trained as mathematicians.
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 limited to 20 words (equivalent to about 80 bytes). Built under the direction of John Mauchly and J. Presper Eckert at the University of Pennsylvania, ENIAC’s 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 power and contained over 18,000 vacuum tubes, 1,500 relays, and hundreds of thousands of resistors, capacitors, and inductors.[94] One of its major engineering feats was to minimize the effects of tube burnout, which was a common problem in machine reliability at that time. The machine was in almost constant use for the next ten years.
Stored-program computer [ edit ]
Early computing machines were programmable in the sense that they could follow the sequence of steps they had been set up to execute, but the “program”, or steps that the machine was to execute, were set up usually by changing how the wires were plugged into a patch panel or plugboard. “Reprogramming”, when it was possible at all, was a laborious process, starting with engineers working out flowcharts, designing the new set up, and then the often-exacting process of physically re-wiring patch panels.[95] Stored-program computers, by contrast, were designed to store a set of instructions (a program), in memory – typically the same memory as stored data.
theory [edit]
The theoretical basis for the stored-program computer had been proposed by Alan Turing in his 1936 paper. In 1945 Turing joined the National Physical Laboratory and began his work on developing an electronic stored-program digital computer. His 1945 report ‘Proposed Electronic Calculator’ was the first specification for such a device.
Meanwhile, John von Neumann at the Moore School of Electrical Engineering, University of Pennsylvania, circulated his First Draft of a Report on the EDVAC in 1945. Although substantially similar to Turing’s design and containing comparatively little engineering detail, the computer architecture it outlined became known as the “von Neumann architecture”. Turing presented a more detailed paper to the National Physical Laboratory (NPL) Executive Committee in 1946, giving the first reasonably complete design of a stored-program computer, a device he called the Automatic Computing Engine (ACE). However, the better-known EDVAC design of John von Neumann, who knew of Turing’s theoretical work, received more publicity, despite its incomplete nature and questionable lack of attribution of the sources of some of the ideas.[49]
Turing thought that the speed and the size of computer memory were crucial elements, so he proposed a high-speed memory of what would today be called 25 KB, accessed at a speed of 1 MHz. The ACE implemented subroutine calls, whereas the EDVAC did not, and the ACE also used Abbreviated Computer Instructions, an early form of programming language.
Manchester Baby [ edit ]
A section of the rebuilt Manchester Baby , the first electronic stored-program computer
The Manchester Baby was the world’s first electronic stored-program computer. It was 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.[96]
The machine was not intended to be a practical computer but was instead designed as a testbed for the Williams tube, the first random-access digital storage device.[97] Invented by Freddie Williams and Tom Kilburn[98][99] at the University of Manchester in 1946 and 1947, it was a cathode-ray tube that used an effect called secondary emission to temporarily store electronic binary data, and was used successfully in several early computers.
Although the computer was small and primitive, it was a proof of concept for solving a single problem; Baby was the first working machine to contain all of the elements essential to a modern electronic computer.[100] As soon as the Baby had demonstrated the feasibility of its design, a project was initiated at the university to develop the design into a more usable computer, the Manchester Mark 1. The Mark 1 in turn quickly became the prototype for the Ferranti Mark 1, the world’s first commercially available general-purpose computer.[101]
The Baby had a 32-bit word length and a memory of 32 words. As it was designed to be the simplest possible stored-program computer, the only arithmetic operations implemented in hardware were subtraction and negation; other arithmetic operations were implemented in software. The first of three programs written for the machine found the highest proper divisor of 218 (262,144), a calculation that was known would take a long time to run—and so prove the computer’s reliability—by testing every integer from 218 − 1 downwards, as division was implemented by repeated subtraction of the divisor. The program consisted of 17 instructions and ran for 52 minutes before reaching the correct answer of 131,072, after the Baby had performed 3.5 million operations (for an effective CPU speed of 1.1 kIPS). The successive approximations to the answer were displayed as the successive positions of a bright dot on the Williams tube.
Manchester Mark 1 [ edit ]
The Experimental machine led on to the development of the Manchester Mark 1 at the University of Manchester.[102] Work began in August 1948, and the first version was operational by April 1949; a program written to search for Mersenne primes ran error-free for nine hours on the night of 16/17 June 1949. The machine’s successful operation was widely reported in the British press, which used the phrase “electronic brain” in describing it to their readers.
The computer is especially historically significant because of its pioneering inclusion of index registers, an innovation which made it easier for a program to read sequentially through an array of words in memory. Thirty-four patents resulted from the machine’s development, and many of the ideas behind its design were incorporated in subsequent commercial products such as the IBM 701 and 702 as well as the Ferranti Mark 1. The chief designers, Frederic C. Williams and Tom Kilburn, concluded from their experiences with the Mark 1 that computers would be used more in scientific roles than in pure mathematics. In 1951 they started development work on Meg, the Mark 1’s successor, which would include a floating-point unit.
EDSAC [ edit ]
EDSAC
The other contender for being the first recognizably modern digital stored-program computer[103] was the EDSAC,[104] designed and constructed by Maurice Wilkes and his team at the University of Cambridge Mathematical Laboratory in England at the University of Cambridge in 1949. The machine was inspired by John von Neumann’s seminal First Draft of a Report on the EDVAC and was one of the first usefully operational electronic digital stored-program computer.[g]
EDSAC ran its first programs on 6 May 1949, when it calculated a table of squares[107] and a list of prime numbers.The EDSAC also served as the basis for the first commercially applied computer, the LEO I, used by food manufacturing company J. Lyons & Co. Ltd. EDSAC 1 was finally shut down on 11 July 1958, having been superseded by EDSAC 2 which stayed in use until 1965.[108]
The “brain” [computer] may one day come down to our level [of the common people] and help with our income-tax and book-keeping calculations. But this is speculation and there is no sign of it so far. British newspaper The Star in a June 1949 news article about the EDSAC computer, long before the era of the personal computers.[109]
EDVAC [ edit ]
EDVAC
ENIAC inventors John Mauchly and J. Presper Eckert proposed the EDVAC’s construction in August 1944, and design work for the EDVAC commenced at the University of Pennsylvania’s Moore School of Electrical Engineering, before the ENIAC was fully operational. The design implemented a number of important architectural and logical improvements conceived during the ENIAC’s construction, and a high-speed serial-access memory.[110] However, Eckert and Mauchly left the project and its construction floundered.
It was finally delivered to the U.S. Army’s Ballistics Research Laboratory at the Aberdeen Proving Ground in August 1949, but due to a number of problems, the computer only began operation in 1951, and then only on a limited basis.
Commercial computers [ edit ]
The first commercial computer was the Ferranti Mark 1, built by Ferranti and delivered to the University of Manchester in February 1951. It was based on the Manchester Mark 1. The main improvements over the Manchester Mark 1 were in the size of the primary storage (using random access Williams tubes), secondary storage (using a magnetic drum), a faster multiplier, and additional instructions. The basic cycle time was 1.2 milliseconds, and a multiplication could be completed in about 2.16 milliseconds. The multiplier used almost a quarter of the machine’s 4,050 vacuum tubes (valves).[111] A second machine was purchased by the University of Toronto, before the design was revised into the Mark 1 Star. At least seven of these later machines were delivered between 1953 and 1957, one of them to Shell labs in Amsterdam.[112]
In October 1947, the directors of J. Lyons & Company, a British catering company famous for its teashops but with strong interests in new office management techniques, decided to take an active role in promoting the commercial development of computers. The LEO I computer (Lyons Electronic Office) became operational in April 1951[113] and ran the world’s first regular routine office computer job. On 17 November 1951, the J. Lyons company began weekly operation of a bakery valuations job on the LEO – the first business application to go live on a stored program computer.[h]
In June 1951, the UNIVAC I (Universal Automatic Computer) was delivered to the U.S. Census Bureau. Remington Rand eventually sold 46 machines at more than US$1 million each ($10.4 million as of 2022).[114] UNIVAC was the first “mass produced” computer. It used 5,200 vacuum tubes and consumed 125 kW of power. Its primary storage was serial-access mercury delay lines capable of storing 1,000 words of 11 decimal digits plus sign (72-bit words).
IBM introduced a smaller, more affordable computer in 1954 that proved very popular.[i][116] The IBM 650 weighed over 900 kg, the attached power supply weighed around 1350 kg and both were held in separate cabinets of roughly 1.5 × 0.9 × 1.8 m. The system cost US$500,000[117] ($5.05 million as of 2022) or could be leased for US$3,500 a month ($40,000 as of 2022).[114] Its drum memory was originally 2,000 ten-digit words, later expanded to 4,000 words. Memory limitations such as this were to dominate programming for decades afterward. The program instructions were fetched from the spinning drum as the code ran. Efficient execution using drum memory was provided by a combination of hardware architecture – the instruction format included the address of the next instruction – and software: the Symbolic Optimal Assembly Program, SOAP,[118] assigned instructions to the optimal addresses (to the extent possible by static analysis of the source program). Thus many instructions were, when needed, located in the next row of the drum to be read and additional wait time for drum rotation was reduced.
Microprogramming [ edit ]
In 1951, British scientist Maurice Wilkes developed the concept of microprogramming from the realisation that the central processing unit of a computer could be controlled by a miniature, highly specialized computer program in high-speed ROM. Microprogramming allows the base instruction set to be defined or extended by built-in programs (now called firmware or microcode).[119] This concept greatly simplified CPU development. He first described this at the University of Manchester Computer Inaugural Conference in 1951, then published in expanded form in IEEE Spectrum in 1955.[citation needed]
It was widely used in the CPUs and floating-point units of mainframe and other computers; it was implemented for the first time in EDSAC 2,[120] which also used multiple identical “bit slices” to simplify design. Interchangeable, replaceable tube assemblies were used for each bit of the processor.[j]
Magnetic memory [ edit ]
Diagram of a 4×4 plane of magnetic core memory in an X/Y line coincident-current setup. X and Y are drive lines, S is sense, Z is inhibit. Arrows indicate the direction of current for writing.
Magnetic drum memories were developed for the US Navy during WW II with the work continuing at Engineering Research Associates (ERA) in 1946 and 1947. ERA, then a part of Univac included a drum memory in its 1103, announced in February 1953. The first mass-produced computer, the IBM 650, also announced in 1953 had about 8.5 kilobytes of drum memory.
Magnetic core memory patented in 1949[122] with its first usage demonstrated for the Whirlwind computer in August 1953.[123] Commercialization followed quickly. Magnetic core was used in peripherals of the IBM 702 delivered in July 1955, and later in the 702 itself. The IBM 704 (1955) and the Ferranti Mercury (1957) used magnetic-core memory. It went on to dominate the field into the 1970s, when it was replaced with semiconductor memory. Magnetic core peaked in volume about 1975 and declined in usage and market share thereafter.[124]
As late as 1980, PDP-11/45 machines using magnetic-core main memory and drums for swapping were still in use at many of the original UNIX sites.
Early digital computer characteristics [ edit ]
Transistor computers [ edit ]
The bipolar transistor was invented in 1947. From 1955 onward transistors replaced vacuum tubes in computer designs,[126] giving rise to the “second generation” of computers. Compared to 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 service life. Transistorized computers could contain tens of thousands of binary logic circuits in a relatively compact space. Transistors greatly reduced computers’ size, initial cost, and operating cost. Typically, second-generation computers were composed of large numbers of printed circuit boards such as the IBM Standard Modular System, each carrying one to four logic gates or flip-flops.
At the University of Manchester, a team under the leadership of Tom Kilburn designed and built a machine using the newly developed transistors instead of valves. Initially the only devices available were germanium point-contact transistors, less reliable than the valves they replaced but which consumed far less power. Their first transistorized computer, and the first in the world, was operational by 1953,[129] and a second version was completed there in April 1955. The 1955 version used 200 transistors, 1,300 solid-state diodes, and had a power consumption of 150 watts. However, the machine did make use of valves to generate its 125 kHz clock waveforms and in the circuitry to read and write on its magnetic drum memory, so it was not the first completely transistorized computer.
That distinction goes to the Harwell CADET of 1955,[131] built by the electronics division of the Atomic Energy Research Establishment at Harwell. The design featured a 64-kilobyte magnetic drum memory store with multiple moving heads that had been designed at the National Physical Laboratory, UK. By 1953 this team had transistor circuits operating to read and write on a smaller magnetic drum from the Royal Radar Establishment. The machine used a low clock speed of only 58 kHz to avoid having to use any valves to generate the clock waveforms.[132][131]
CADET used 324-point-contact transistors provided by the UK company Standard Telephones and Cables; 76 junction transistors were used for the first stage amplifiers for data read from the drum, since point-contact transistors were too noisy. From August 1956 CADET was offering a regular computing service, during which it often executed continuous computing runs of 80 hours or more.[133][134] Problems with the reliability of early batches of point contact and alloyed junction transistors meant that the machine’s mean time between failures was about 90 minutes, but this improved once the more reliable bipolar junction transistors became available.[135]
The Manchester University Transistor Computer’s design was adopted by the local engineering firm of Metropolitan-Vickers in their Metrovick 950, the first commercial transistor computer anywhere.[136] Six Metrovick 950s were built, the first completed in 1956. They were successfully deployed within various departments of the company and were in use for about five years. A second generation computer, the IBM 1401, captured about one third of the world market. IBM installed more than ten thousand 1401s between 1960 and 1964.
Transistor peripherals [ edit ]
Transistorized electronics improved not only the CPU (Central Processing Unit), but also the peripheral devices. The second generation disk data storage units were able to store tens of millions of letters and digits. Next to the fixed disk storage units, connected to the CPU via high-speed data transmission, were removable disk data storage units. A removable disk pack can be easily exchanged with another pack in a few seconds. Even if the removable disks’ capacity is smaller than fixed disks, their interchangeability guarantees a nearly unlimited quantity of data close at hand. Magnetic tape provided archival capability for this data, at a lower cost than disk.
Many second-generation CPUs delegated peripheral device communications to a secondary processor. For example, while the communication processor controlled card reading and punching, the main CPU executed calculations and binary branch instructions. One databus would bear data between the main CPU and core memory at the CPU’s fetch-execute cycle rate, and other databusses would typically serve the peripheral devices. On the PDP-1, the core memory’s cycle time was 5 microseconds; consequently most arithmetic instructions took 10 microseconds (100,000 operations per second) because most operations took at least two memory cycles; one for the instruction, one for the operand data fetch.
During the second generation remote terminal units (often in the form of Teleprinters like a Friden Flexowriter) saw greatly increased use.[k] Telephone connections provided sufficient speed for early remote terminals and allowed hundreds of kilometers separation between remote-terminals and the computing center. Eventually these stand-alone computer networks would be generalized into an interconnected network of networks—the Internet.[l]
Transistor supercomputers [ edit ]
The University of Manchester Atlas in January 1963
The early 1960s saw the advent of supercomputing. The Atlas was a joint development between the University of Manchester, Ferranti, and Plessey, and was first installed at Manchester University and officially commissioned in 1962 as one of the world’s first supercomputers – considered to be the most powerful computer in the world at that time.[139] It was said that whenever Atlas went offline half of the United Kingdom’s computer capacity was lost.[140] It was a second-generation machine, using discrete germanium transistors. Atlas also pioneered the Atlas Supervisor, “considered by many to be the first recognisable modern operating system”.[141]
In the US, a series of computers at Control Data Corporation (CDC) were designed by Seymour Cray to use innovative designs and parallelism to achieve superior computational peak performance.[142] The CDC 6600, released in 1964, is generally considered the first supercomputer.[143][144] The CDC 6600 outperformed its predecessor, the IBM 7030 Stretch, by about a factor of 3. With performance of about 1 megaFLOPS, the CDC 6600 was the world’s fastest computer from 1964 to 1969, when it relinquished that status to its successor, the CDC 7600.
Integrated circuit computers [ edit ]
The “third-generation” of digital electronic computers used integrated circuit (IC) chips as the basis of their logic.
The idea of an integrated circuit was conceived by a radar scientist working for the Royal Radar Establishment of the Ministry of Defence, Geoffrey W.A. Dummer.
The first working integrated circuits were invented by Jack Kilby at Texas Instruments and Robert Noyce at Fairchild Semiconductor.[145] Kilby recorded his initial ideas concerning the integrated circuit in July 1958, successfully demonstrating the first working integrated example on 12 September 1958.[146] Kilby’s invention was a hybrid integrated circuit (hybrid IC).[147] It had external wire connections, which made it difficult to mass-produce.[148]
Noyce came up with his own idea of an integrated circuit half a year after Kilby.[149] Noyce’s invention was a monolithic integrated circuit (IC) chip.[150][148] His chip solved many practical problems that Kilby’s had not. Produced at Fairchild Semiconductor, it was made of silicon, whereas Kilby’s chip was made of germanium. The basis for Noyce’s monolithic IC was Fairchild’s planar process, which allowed integrated circuits to be laid out using the same principles as those of printed circuits. The planar process was developed by Noyce’s colleague Jean Hoerni in early 1959, based on Mohamed M. Atalla’s work on semiconductor surface passivation by silicon dioxide at Bell Labs in the late 1950s.[151][152][153]
Third generation (integrated circuit) computers first appeared in the early 1960s in computers developed for government purposes, and then in commercial computers beginning in the mid-1960s. The first silicon IC computer was the Apollo Guidance Computer or AGC.[154] Although not the most powerful computer of its time, the extreme constraints on size, mass, and power of the Apollo spacecraft required the AGC to be much smaller and denser than any prior computer, weighing in at only 70 pounds (32 kg). Each lunar landing mission carried two AGCs, one each in the command and lunar ascent modules.
Semiconductor memory [ edit ]
The MOSFET (metal-oxide-semiconductor field-effect transistor, or MOS transistor) was invented by Mohamed M. Atalla and Dawon Kahng at Bell Labs in 1959.[155] In addition to data processing, the MOSFET enabled the practical use of MOS transistors as memory cell storage elements, a function previously served by magnetic cores. Semiconductor memory, also known as MOS memory, was cheaper and consumed less power than magnetic-core memory.[156] MOS random-access memory (RAM), in the form of static RAM (SRAM), was developed by John Schmidt at Fairchild Semiconductor in 1964.[156][157] In 1966, Robert Dennard at the IBM Thomas J. Watson Research Center developed MOS dynamic RAM (DRAM).[158] In 1967, Dawon Kahng and Simon Sze at Bell Labs developed the floating-gate MOSFET, the basis for MOS non-volatile memory such as EPROM, EEPROM and flash memory.[159][160]
Microprocessor computers [ edit ]
The “fourth-generation” of digital electronic computers used microprocessors as the basis of their logic. The microprocessor has origins in the MOS integrated circuit (MOS IC) chip.[161] Due to rapid MOSFET scaling, MOS IC chips rapidly increased in complexity at a rate predicted by Moore’s law, leading to large-scale integration (LSI) with hundreds of transistors on a single MOS chip by the late 1960s. The application of MOS LSI chips to computing was the basis for the first microprocessors, as engineers began recognizing that a complete computer processor could be contained on a single MOS LSI chip.[161]
The subject of exactly which device was the first microprocessor is contentious, partly due to lack of agreement on the exact definition of the term “microprocessor”. The earliest multi-chip microprocessors were the Four-Phase Systems AL-1 in 1969 and Garrett AiResearch MP944 in 1970, developed with multiple MOS LSI chips.[161] The first single-chip microprocessor was the Intel 4004, developed on a single PMOS LSI chip.[161] It was designed and realized by Ted Hoff, Federico Faggin, Masatoshi Shima and Stanley Mazor at Intel, and released in 1971.[m] Tadashi Sasaki and Masatoshi Shima at Busicom, a calculator manufacturer, had the initial insight that the CPU could be a single MOS LSI chip, supplied by Intel.[164]
The die from an Intel 8742 , an 8-bit microcontroller that includes a CPU running at 12 MHz, RAM, EPROM, and I/O
While the earliest microprocessor ICs literally contained only the processor, i.e. the central processing unit, of a computer, their progressive development naturally led to chips containing most or all of the internal electronic parts of a computer. The integrated circuit in the image on the right, for example, an Intel 8742, is an 8-bit microcontroller that includes a CPU running at 12 MHz, 128 bytes of RAM, 2048 bytes of EPROM, and I/O in the same chip.
During the 1960s there was considerable overlap between second and third generation technologies.[n] IBM implemented its IBM Solid Logic Technology modules in hybrid circuits for the IBM System/360 in 1964. As late as 1975, Sperry Univac continued the manufacture of second-generation machines such as the UNIVAC 494. The Burroughs large systems such as the B5000 were stack machines, which allowed for simpler programming. These pushdown automatons were also implemented in minicomputers and microprocessors later, which influenced programming language design. Minicomputers served as low-cost computer centers for industry, business and universities.[165] It became possible to simulate analog circuits with the simulation program with integrated circuit emphasis, or SPICE (1971) on minicomputers, one of the programs for electronic design automation (EDA). The microprocessor led to the development of microcomputers, small, low-cost computers that could be owned by individuals and small businesses. Microcomputers, the first of which appeared in the 1970s, became ubiquitous in the 1980s and beyond.
Altair 8800
While which specific system is considered the first microcomputer is a matter of debate, as there were several unique hobbyist systems developed based on the Intel 4004 and its successor, the Intel 8008, the first commercially available microcomputer kit was the Intel 8080-based Altair 8800, which was announced in the January 1975 cover article of Popular Electronics. However, this was an extremely limited system in its initial stages, having only 256 bytes of DRAM in its initial package and no input-output except its toggle switches and LED register display. Despite this, it was initially surprisingly popular, with several hundred sales in the first year, and demand rapidly outstripped supply. Several early third-party vendors such as Cromemco and Processor Technology soon began supplying additional S-100 bus hardware for the Altair 8800.
In April 1975 at the Hannover Fair, Olivetti presented the P6060, the world’s first complete, pre-assembled personal computer system. The central processing unit consisted of two cards, code named PUCE1 and PUCE2, and unlike most other personal computers was built with TTL components rather than a microprocessor. It had one or two 8″ floppy disk drives, a 32-character plasma display, 80-column graphical thermal printer, 48 Kbytes of RAM, and BASIC language. It weighed 40 kg (88 lb). As a complete system, this was a significant step from the Altair, though it never achieved the same success. It was in competition with a similar product by IBM that had an external floppy disk drive.
From 1975 to 1977, most microcomputers, such as the MOS Technology KIM-1, the Altair 8800, and some versions of the Apple I, were sold as kits for do-it-yourselfers. Pre-assembled systems did not gain much ground until 1977, with the introduction of the Apple II, the Tandy TRS-80, the first SWTPC computers, and the Commodore PET. Computing has evolved with microcomputer architectures, with features added from their larger brethren, now dominant in most market segments.
A NeXT Computer and its object-oriented development tools and libraries were used by Tim Berners-Lee and Robert Cailliau at CERN to develop the world’s first web server software, CERN httpd, and also used to write the first web browser, WorldWideWeb.
Systems as complicated as computers require very high reliability. ENIAC remained on, in continuous operation from 1947 to 1955, for eight years before being shut down. Although a vacuum tube might fail, it would be replaced without bringing down the system. By the simple strategy of never shutting down ENIAC, the failures were dramatically reduced. The vacuum-tube SAGE air-defense computers became remarkably reliable – installed in pairs, one off-line, tubes likely to fail did so when the computer was intentionally run at reduced power to find them. Hot-pluggable hard disks, like the hot-pluggable vacuum tubes of yesteryear, continue the tradition of repair during continuous operation. Semiconductor memories routinely have no errors when they operate, although operating systems like Unix have employed memory tests on start-up to detect failing hardware. Today, the requirement of reliable performance is made even more stringent when server farms are the delivery platform.[166] Google has managed this by using fault-tolerant software to recover from hardware failures, and is even working on the concept of replacing entire server farms on-the-fly, during a service event.[167][168]
In the 21st century, multi-core CPUs became commercially available.[169] Content-addressable memory (CAM)[170] has become inexpensive enough to be used in networking, and is frequently used for on-chip cache memory in modern microprocessors, although no computer system has yet implemented hardware CAMs for use in programming languages. Currently, CAMs (or associative arrays) in software are programming-language-specific. Semiconductor memory cell arrays are very regular structures, and manufacturers prove their processes on them; this allows price reductions on memory products. During the 1980s, CMOS logic gates developed into devices that could be made as fast as other circuit types; computer power consumption could therefore be decreased dramatically. Unlike the continuous current draw of a gate based on other logic types, a CMOS gate only draws significant current during the ‘transition’ between logic states, except for leakage.
CMOS circuits have allowed computing to become a commodity which is now ubiquitous, embedded in many forms, from greeting cards and telephones to satellites. The thermal design power which is dissipated during operation has become as essential as computing speed of operation. In 2006 servers consumed 1.5% of the total energy budget of the U.S.[171] The energy consumption of computer data centers was expected to double to 3% of world consumption by 2011. The SoC (system on a chip) has compressed even more of the integrated circuitry into a single chip; SoCs are enabling phones and PCs to converge into single hand-held wireless mobile devices.[172]
Quantum computing is an emerging technology in the field of computing. MIT Technology Review reported 10 November 2017 that IBM has created a 50-qubit computer; currently its quantum state lasts 50 microseconds.[173] Google researchers have been able to extend the 50 microsecond time limit, as reported 14 July 2021 in Nature;[174] stability has been extended 100-fold by spreading a single logical qubit over chains of data qubits for quantum error correction.[174] Physical Review X reported a technique for ‘single-gate sensing as a viable readout method for spin qubits’ (a singlet-triplet spin state in silicon) on 26 November 2018.[175] A Google team has succeeded in operating their RF pulse modulator chip at 3 Kelvin, simplifying the cryogenics of their 72-qubit computer, which is setup to operate at 0.3 Kelvin; but the readout circuitry and another driver remain to be brought into the cryogenics.[176][o] See: Quantum supremacy[178][179] Silicon qubit systems have demonstrated entanglement at non-local distances.[180]
Computing hardware and its software have even become a metaphor for the operation of the universe.[181]
Epilogue [ edit ]
An indication of the rapidity of development of this field can be inferred from the history of the seminal 1947 article by Burks, Goldstine and von Neumann.[182] By the time that anyone had time to write anything down, it was obsolete. After 1945, others read John von Neumann’s First Draft of a Report on the EDVAC, and immediately started implementing their own systems. To this day, the rapid pace of development has continued, worldwide.[183][p]
See also[edit]
Notes [edit]
References[ edit ]
Linux Mint
Mint has become the ultimate example of what a Linux desktop should be: fast, simple, beautiful, useful, and productive. Still others see Mint as the ideal desktop for Windows refugees or those trying Linux for the first time and want an operating system that essentially works out of the box.
David Hayward
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Definition from WhatIs.com
In computing, data is information that has been translated into a form that is efficient for movement or processing. Relative to today’s computers and transmission media, data is information converted into a binary digital form. It is acceptable for dates to be used as a singular subject or plural subject. Raw data is a term used to describe data in its most basic digital format.
The concept of data in the context of computers has its roots in the work of Claude Shannon, an American mathematician known as the father of information theory. He introduced binary digital concepts based on the application of two-valued Boolean logic to electronic circuits. Binary digit formats underlie the CPUs, semiconductor memories, and disk drives, as well as many of the peripheral devices that are common in computing today. Early computer inputs for control and data took the form of punched cards, followed by magnetic tape and the hard disk.
The importance of data in enterprise computing was illustrated early on by the popularity of the terms “computing” and “electronic computing,” which for a time encompassed the full gamut of what is now known as information technology. Specialization has occurred throughout the history of enterprise computing, and as enterprise computing has grown, a distinct data profession has emerged.
How data is stored Computers represent data, including video, images, sounds, and text, as binary values using patterns of just two numbers: 1 and 0. A bit is the smallest unit of data and represents only a single value. A byte is eight binary digits long. Storage and RAM are measured in megabytes and gigabytes. The units of measure for data continue to increase as the amount of data collected and stored increases. For example, the relatively new term brontobyte stands for data storage equal to 1027 to the 10th power of bytes. Data can be stored in file formats such as in mainframe systems using ISAM and VSAM. Other file formats for data storage, conversion, and processing include comma-separated values. These formats continued to be used on a variety of machine types even as more structured-data approaches took hold in enterprise computing. A larger specialization emerged, developed as a database, database management system, and then relational database technology to organize information. The realm of digital data has grown over time from bits and bytes to brontobytes, with even greater amounts of data to come.
Types of Data The growth of the internet and smartphones over the past decade has led to an increase in digital data creation. Data now includes text, audio, and video information, as well as log and web activity records. Much of this is unstructured data. The term big data has been used to describe data in the petabyte range or larger. A short version shows big data with 3Vs – volume, variety and speed. With the spread of web-based e-commerce, big data-driven business models have emerged that treat data as an asset in its own right. Such trends have also led to increased concern about the societal use of data and privacy. Data has meaning beyond its use in computer applications geared towards data processing. For example, in the connection of electronic components and network communication, the term data is often distinguished from “control information”, “control bits” and similar terms to identify the main content of a transmission unit. In addition, the term data is used in science to describe a collection of facts. This also applies to areas such as finance, marketing, demographics and health.
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