1.
Hewlett-Packard
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The Hewlett-Packard Company or shortened to Hewlett-Packard was an American multinational information technology company headquartered in Palo Alto, California. The company was founded in a garage in Palo Alto by William Bill Redington Hewlett and David Dave Packard. HP was the worlds leading PC manufacturer from 2007 to Q22013 and it specialized in developing and manufacturing computing, data storage, and networking hardware, designing software and delivering services. HP also had services and consulting business around its products and partner products.4 billion in 2008, in November 2009, HP announced the acquisition of 3Com, with the deal closing on April 12,2010. On April 28,2010, HP announced the buyout of Palm, on September 2,2010, HP won its bidding war for 3PAR with a $33 a share offer, which Dell declined to match. On October 6,2014, Hewlett-Packard announced plans to split the PC and printers business from its enterprise products, the split closed on November 1,2015, and resulted in two publicly traded companies, HP Inc. and Hewlett Packard Enterprise. William Redington Hewlett and David Packard graduated with degrees in engineering from Stanford University in 1935. The company originated in a garage in nearby Palo Alto during a fellowship they had with a past professor, Terman was considered a mentor to them in forming Hewlett-Packard. In 1939, Packard and Hewlett established Hewlett-Packard in Packards garage with a capital investment of US$538. Hewlett and Packard tossed a coin to decide whether the company they founded would be called Hewlett-Packard or Packard-Hewlett, HP incorporated on August 18,1947, and went public on November 6,1957. Of the many projects they worked on, their very first financially successful product was an audio oscillator. This allowed them to sell the Model 200A for $54.40 when competitors were selling less stable oscillators for over $200, the Model 200 series of generators continued until at least 1972 as the 200AB, still tube-based but improved in design through the years. They worked on technology and artillery shell fuses during World War II. Hewlett-Packards HP Associates division, established around 1960, developed semiconductor devices primarily for internal use, instruments and calculators were some of the products using these devices. HP partnered in the 1960s with Sony and the Yokogawa Electric companies in Japan to develop several high-quality products, the products were not a huge success, as there were high costs in building HP-looking products in Japan. HP and Yokogawa formed a joint venture in 1963 to market HP products in Japan, HP bought Yokogawa Electrics share of Hewlett-Packard Japan in 1999. HP spun off a company, Dynac, to specialize in digital equipment. The name was picked so that the HP logo hp could be turned upside down to be a reverse image of the logo dy of the new company
2.
Calculator
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An electronic calculator is a small, portable electronic device used to perform operations ranging from basic arithmetic to complex mathematics. The first solid state electronic calculator was created in the 1960s, building on the history of tools such as the abacus. It was developed in parallel with the computers of the day. The pocket sized devices became available in the 1970s, especially after the first microprocessor and they later became used commonly within the petroleum industry. Modern electronic calculators vary, from cheap, give-away, credit-card-sized models to sturdy desktop models with built-in printers and they became popular in the mid-1970s. By the end of decade, calculator prices had reduced to a point where a basic calculator was affordable to most. In addition to general purpose calculators, there are designed for specific markets. For example, there are scientific calculators which include trigonometric and statistical calculations, some calculators even have the ability to do computer algebra. Graphing calculators can be used to graph functions defined on the real line, as of 2016, basic calculators cost little, but the scientific and graphing models tend to cost more. In 1986, calculators still represented an estimated 41% of the worlds general-purpose hardware capacity to compute information, by 2007, this diminished to less than 0. 05%. Modern 2016 electronic calculators contain a keyboard with buttons for digits and arithmetical operations, most basic calculators assign only one digit or operation on each button, however, in more specific calculators, a button can perform multi-function working with key combinations. Large-sized figures and comma separators are used to improve readability. Various symbols for function commands may also be shown on the display, fractions such as 1⁄3 are displayed as decimal approximations, for example rounded to 0.33333333. Also, some fractions can be difficult to recognize in decimal form, as a result, Calculators also have the ability to store numbers into computer memory. Basic types of these only one number at a time. The variables can also be used for constructing formulas, some models have the ability to extend memory capacity to store more numbers, the extended memory address is termed an array index. Power sources of calculators are, batteries, solar cells or mains electricity, some models even have no turn-off button but they provide some way to put off. Crank-powered calculators were also common in the computer era
3.
Commodore International
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Commodore International was a North American home computer and electronics manufacturer. Commodore International, along with its subsidiary Commodore Business Machines, participated in the development of the computer industry in the 1970s and 1980s. The company developed and marketed one of the worlds best-selling desktop computers, the company that would become Commodore Business Machines, Inc. was founded in 1954 in Toronto as the Commodore Portable Typewriter Company by Polish immigrant and Auschwitz survivor Jack Tramiel. He moved to Toronto to start production, by the late 1950s a wave of Japanese machines forced most North American typewriter companies to cease business, but Tramiel instead turned to adding machines. In 1955, the company was incorporated as Commodore Business Machines. In 1962, Commodore went public on the New York Stock Exchange, in the late 1960s, history repeated itself when Japanese firms started producing and exporting adding machines. The companys main investor and chairman, Irving Gould, suggested that Tramiel travel to Japan to understand how to compete, instead, he returned with the new idea to produce electronic calculators, which were just coming on the market. Commodore soon had a profitable calculator line and was one of the popular brands in the early 1970s. However, in 1975, Texas Instruments, the supplier of calculator parts, entered the market directly. Commodore obtained an infusion of cash from Gould, which Tramiel used beginning in 1976 to purchase several second-source chip suppliers, including MOS Technology, Inc. in order to assure his supply. He agreed to buy MOS, which was having troubles of its own, through the 1970s, Commodore also produced numerous peripherals and consumer electronic products such as the Chessmate, a chess computer based around a MOS6504 chip, released in 1978. In December 2007 when Tramiel was visiting the Computer History Museum in Mountain View, California, for the 25th anniversary of the Commodore 64 and he said, I wanted to call my company General, but theres so many Generals in the U. S. Then I went to Admiral, but that was taken, so I wind up in Berlin, Germany, with my wife, and we were in a cab, and the cab made a short stop, and in front of us was an Opel Commodore. Tramiel gave this account in interviews, but Opels Commodore didnt debut until 1967. Once Chuck Peddle had taken over engineering at Commodore, he convinced Jack Tramiel that calculators were already a dead end, from PETs 1977 debut, Commodore would be a computer company. The operational headquarters, where research and development of new products occurred, retained the name Commodore Business Machines, in 1980 Commodore launched production for the European market in Braunschweig. By 1980 Commodore was one of the three largest microcomputer companies, and the largest in the Common Market and this was addressed with the introduction of the VIC-20 in 1981, which was introduced at a cost of US$299 and sold in retail stores. Commodore took out ads featuring William Shatner asking consumers Why buy just a video game
4.
Casio
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Casio Computer Co. Ltd. is a multinational consumer electronics and commercial electronics manufacturing company headquartered in Shibuya, Tokyo, Japan. Its products include calculators, mobile phones, digital cameras, electronic musical instruments and it was founded in 1946, and in 1957 released the worlds first entirely electric compact calculator. Casio was a digital camera innovator, and during the 1980s and 1990s. Casio was established in April 1946 by Tadao Kashio, an engineer specializing in fabrication technology. Kashios first major product was the pipe, a finger ring that would hold a cigarette. Japan was impoverished immediately following World War II, so cigarettes were valuable, after seeing the electric calculators at the first Business Show in Ginza, Tokyo in 1949, Kashio and his younger brothers used their profits from the yubiwa pipe to develop their own calculators. Most of the calculators at that time worked using gears and could be operated by using a crank or using a motor. Toshio possessed some knowledge of electronics, and set out to make a calculator using solenoids, the desk-sized calculator was finished in 1954 and was Japans first electro-mechanical calculator. Another distinguishing innovation was the use of a display window instead of the three display windows used in other calculators. In 1957 Casio released the Model 14-A, sold for 485,000 yen, the worlds first all-electric compact calculator,1957 also marked the establishment of Casio Computer Co. Ltd. In the 1980s, its budget electronic instruments and its line of home electronic musical keyboard instruments became popular. The company also became known for the wide variety and innovation of its wristwatches. It was one of the earliest manufacturers of quartz watches, both digital and analog and it also began selling calculator watches during this time. In the 1970s and 80s, Casio was known for its electronic calculators, today, Casio is most commonly known for making durable and reliable digital watches. The G-Shock range of shock resistant watches is popular, with the 1983 G-Shock DW-5600C being highly sought-after by collectors, Casio made a variety of digital watches with in-built games in the 1980s and 90s, which were highly popular at the time. Casio also makes products for local markets, including a Prayer Compass watch designed to help Muslims pray on time, note, This is a list of selected calculators. Figures in parentheses imply approximate year of introduction, note, This is a list of selected models. Wiki collection of works on Casio
5.
Speed of light
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The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its exact value is 299792458 metres per second, it is exact because the unit of length, the metre, is defined from this constant, according to special relativity, c is the maximum speed at which all matter and hence information in the universe can travel. It is the speed at which all particles and changes of the associated fields travel in vacuum. Such particles and waves travel at c regardless of the motion of the source or the reference frame of the observer. In the theory of relativity, c interrelates space and time, the speed at which light propagates through transparent materials, such as glass or air, is less than c, similarly, the speed of radio waves in wire cables is slower than c. The ratio between c and the speed v at which light travels in a material is called the index n of the material. In communicating with distant space probes, it can take minutes to hours for a message to get from Earth to the spacecraft, the light seen from stars left them many years ago, allowing the study of the history of the universe by looking at distant objects. The finite speed of light limits the theoretical maximum speed of computers. The speed of light can be used time of flight measurements to measure large distances to high precision. Ole Rømer first demonstrated in 1676 that light travels at a speed by studying the apparent motion of Jupiters moon Io. In 1865, James Clerk Maxwell proposed that light was an electromagnetic wave, in 1905, Albert Einstein postulated that the speed of light c with respect to any inertial frame is a constant and is independent of the motion of the light source. He explored the consequences of that postulate by deriving the theory of relativity and in doing so showed that the parameter c had relevance outside of the context of light and electromagnetism. After centuries of increasingly precise measurements, in 1975 the speed of light was known to be 299792458 m/s with a measurement uncertainty of 4 parts per billion. In 1983, the metre was redefined in the International System of Units as the distance travelled by light in vacuum in 1/299792458 of a second, as a result, the numerical value of c in metres per second is now fixed exactly by the definition of the metre. The speed of light in vacuum is usually denoted by a lowercase c, historically, the symbol V was used as an alternative symbol for the speed of light, introduced by James Clerk Maxwell in 1865. In 1856, Wilhelm Eduard Weber and Rudolf Kohlrausch had used c for a different constant later shown to equal √2 times the speed of light in vacuum, in 1894, Paul Drude redefined c with its modern meaning. Einstein used V in his original German-language papers on special relativity in 1905, but in 1907 he switched to c, sometimes c is used for the speed of waves in any material medium, and c0 for the speed of light in vacuum. This article uses c exclusively for the speed of light in vacuum, since 1983, the metre has been defined in the International System of Units as the distance light travels in vacuum in 1⁄299792458 of a second
6.
Texas Instruments
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Texas Instruments Inc. is an American technology company that designs and manufactures semiconductors, which it sells to electronics designers and manufacturers globally. Headquartered in Dallas, Texas, United States, TI is one of the top ten semiconductor companies worldwide, Texas Instrumentss focus is on developing analog chips and embedded processors, which accounts for more than 85% of their revenue. TI also produces TI digital light processing technology and education technology products including calculators, microcontrollers, to date, TI has more than 43,000 patents worldwide. TI produced the worlds first commercial silicon transistor in 1950, Jack Kilby invented the integrated circuit in 1958 while working at TIs Central Research Labs. TI also invented the hand-held calculator in 1967, and introduced the first single-chip microcontroller in 1970, in 1987, TI invented the digital light processing device, which serves as the foundation for the companys award-winning DLP technology and DLP Cinema. In 1990, TI came out with the popular TI-81 calculator which made them a leader in the calculator industry. In 1997, its business was sold to Raytheon, which allowed TI to strengthen its focus on digital solutions. Texas Instruments was founded by Cecil H. Green, J. Erik Jonsson, Eugene McDermott, McDermott was one of the original founders of Geophysical Service Inc. in 1930. McDermott, Green, and Jonsson were GSI employees who purchased the company in 1941, in November,1945, Patrick Haggerty was hired as general manager of the Laboratory and Manufacturing division, which focused on electronic equipment. By 1951, the L&M division, with its contracts, was growing faster than GSIs Geophysical division. The company was reorganized and initially renamed General Instruments Inc, because there already existed a firm named General Instrument, the company was renamed Texas Instruments that same year. From 1956 to 1961, Fred Agnich of Dallas, later a Republican member of the Texas House of Representatives, was the Texas Instruments president, Geophysical Service, Inc. became a subsidiary of Texas Instruments. Early in 1988 most of GSI was sold to the Halliburton Company, in 1930, J. Clarence Karcher and Eugene McDermott founded Geophysical Service, an early provider of seismic exploration services to the petroleum industry. In 1939, the company reorganized as Coronado Corp. an oil company with Geophysical Service Inc, on December 6,1941, McDermott along with three other GSI employees, J. Erik Jonsson, Cecil H. Green, and H. B. During World War II, GSI expanded their services to include electronics for the U. S. Army, Signal Corps, in 1951, the company changed its name to Texas Instruments, GSI becoming a wholly owned subsidiary of the new company. Texas Instruments also continued to manufacture equipment for use in the seismic industry, after selling GSI, TI finally sold the company to Halliburton in 1988, at which point GSI ceased to exist as a separate entity. Texas Instruments entered the electronics market in 1942 with submarine detection equipment. During the early 1980s, Texas Instruments instituted a quality program which included Juran training, as well as promoting statistical process control, Taguchi methods and Design for Six Sigma
7.
TI-30
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The TI-30 was a scientific calculator manufactured by Texas Instruments, the first model of which was introduced in 1976. While the original TI-30 left production in 1983 after several revisions, TI maintains the TI-30 designation as a branding for its low. The original TI-30 was notable for its low cost for the time. This was much less than the prices of other scientific calculators of the era, for example. The Casio FX-20, another popular scientific calculator, sold for roughly double the price of the TI-30, the TI-30 sold for less than the cost of a professional grade slide rule. The TI-30 sold an estimated 15 million units during its lifespan from 1976–1983, although the MSRP in the US was US$24.95 at introduction, it is rumored that the original TI-30 got its name from a planned retail price of US$29.95 or $30. The TI-30 could perform all the logarithmic and trigonometric functions of an HP-21. Although the Texas Instruments SR-50 pioneered algebraic notation with precedence and parentheses in 1974, early production TI-30 units contained a logic error in their calculation of inverse tangents. On these early models, pressing 0 INV TAN would cause the calculator to go into a loop until it was powered off with the OFF button. The 0 had to be pressed on the keyboard, the calculator produced a correct answer if the 0 was the result of a previous calculation, the TI-30 was at one point the most popular scientific calculator for junior high and high school use in the United States. The book alone retailed for $12.95 and many considered the book to be more valuable than the calculator itself. In 1980, Texas Instruments converted the TI-30 to use a liquid crystal display, releasing the TI-30 LCD in Europe and the TI-30 II a year later in the U. S. The calculator itself remained functionally similar over several redesigns in the few years. The earliest model, however, ran off of a 9 volt battery, the low cost, bulky case and easily accessible matrix keyboard made the TI-30 ideal for homebrew electronics projects requiring a large number of keys in a small package. Currently the bottom of the TI-30 line, the Xa has a standard one-line, the solar-powered eco RS model is available only in Europe. TI-30Xa Solar School Edition, A modified version of the TI-30Xa and this calculator is approved for Virginia State Testing. TI-30X IIS and TI-30X IIB, added a two-line, scrollable display, tI-30XS and TI-30XB MultiView, first non-graphing TI calculators with a dot-matrix display, able to display expressions in textbook-style notation. Uses a command similar to TI-BASIC, but with no programming capability
8.
Floating-point arithmetic
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In computing, floating-point arithmetic is arithmetic using formulaic representation of real numbers as an approximation so as to support a trade-off between range and precision. A number is, in general, represented approximately to a number of significant digits and scaled using an exponent in some fixed base. For example,1.2345 =12345 ⏟ significand ×10 ⏟ base −4 ⏞ exponent, the term floating point refers to the fact that a numbers radix point can float, that is, it can be placed anywhere relative to the significant digits of the number. This position is indicated as the exponent component, and thus the floating-point representation can be thought of as a kind of scientific notation. The result of dynamic range is that the numbers that can be represented are not uniformly spaced. Over the years, a variety of floating-point representations have been used in computers, however, since the 1990s, the most commonly encountered representation is that defined by the IEEE754 Standard. A floating-point unit is a part of a computer system designed to carry out operations on floating point numbers. A number representation specifies some way of encoding a number, usually as a string of digits, there are several mechanisms by which strings of digits can represent numbers. In common mathematical notation, the string can be of any length. If the radix point is not specified, then the string implicitly represents an integer, in fixed-point systems, a position in the string is specified for the radix point. So a fixed-point scheme might be to use a string of 8 decimal digits with the point in the middle. The scaling factor, as a power of ten, is then indicated separately at the end of the number, floating-point representation is similar in concept to scientific notation. Logically, a floating-point number consists of, A signed digit string of a length in a given base. This digit string is referred to as the significand, mantissa, the length of the significand determines the precision to which numbers can be represented. The radix point position is assumed always to be somewhere within the significand—often just after or just before the most significant digit and this article generally follows the convention that the radix point is set just after the most significant digit. A signed integer exponent, which modifies the magnitude of the number, using base-10 as an example, the number 7005152853504700000♠152853.5047, which has ten decimal digits of precision, is represented as the significand 1528535047 together with 5 as the exponent. In storing such a number, the base need not be stored, since it will be the same for the range of supported numbers. Symbolically, this value is, s b p −1 × b e, where s is the significand, p is the precision, b is the base
9.
Binary number
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The base-2 system is a positional notation with a radix of 2. Because of its implementation in digital electronic circuitry using logic gates. Each digit is referred to as a bit, the modern binary number system was devised by Gottfried Leibniz in 1679 and appears in his article Explication de lArithmétique Binaire. Systems related to binary numbers have appeared earlier in multiple cultures including ancient Egypt, China, Leibniz was specifically inspired by the Chinese I Ching. The scribes of ancient Egypt used two different systems for their fractions, Egyptian fractions and Horus-Eye fractions, the method used for ancient Egyptian multiplication is also closely related to binary numbers. This method can be seen in use, for instance, in the Rhind Mathematical Papyrus, the I Ching dates from the 9th century BC in China. The binary notation in the I Ching is used to interpret its quaternary divination technique and it is based on taoistic duality of yin and yang. Eight trigrams and a set of 64 hexagrams, analogous to the three-bit and six-bit binary numerals, were in use at least as early as the Zhou Dynasty of ancient China. The Song Dynasty scholar Shao Yong rearranged the hexagrams in a format that resembles modern binary numbers, the Indian scholar Pingala developed a binary system for describing prosody. He used binary numbers in the form of short and long syllables, Pingalas Hindu classic titled Chandaḥśāstra describes the formation of a matrix in order to give a unique value to each meter. The binary representations in Pingalas system increases towards the right, the residents of the island of Mangareva in French Polynesia were using a hybrid binary-decimal system before 1450. Slit drums with binary tones are used to encode messages across Africa, sets of binary combinations similar to the I Ching have also been used in traditional African divination systems such as Ifá as well as in medieval Western geomancy. The base-2 system utilized in geomancy had long been applied in sub-Saharan Africa. Leibnizs system uses 0 and 1, like the modern binary numeral system, Leibniz was first introduced to the I Ching through his contact with the French Jesuit Joachim Bouvet, who visited China in 1685 as a missionary. Leibniz saw the I Ching hexagrams as an affirmation of the universality of his own beliefs as a Christian. Binary numerals were central to Leibnizs theology and he believed that binary numbers were symbolic of the Christian idea of creatio ex nihilo or creation out of nothing. Is not easy to impart to the pagans, is the ex nihilo through Gods almighty power. In 1854, British mathematician George Boole published a paper detailing an algebraic system of logic that would become known as Boolean algebra
10.
Frequency counter
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A frequency counter is an electronic instrument, or component of one, that is used for measuring frequency. Frequency counters usually measure the number of oscillations or pulses per second in an electronic signal. Such an instrument is referred to as a cymometer, particularly one of Chinese manufacture. Most frequency counters work by using a counter which accumulates the number of events occurring within a period of time. After a preset period known as the time, the value in the counter is transferred to a display. The internal oscillator which provides the signals is called the timebase. If the event to be counted is already in electronic form, more complex signals may need some conditioning to make them suitable for counting. Most general purpose frequency counters will include some form of amplifier, DSP technology, sensitivity control and hysteresis are other techniques to improve performance. Other types of events that are not inherently electronic in nature will need to be converted using some form of transducer. For example, an event could be arranged to interrupt a light beam. Frequency counters designed for radio frequencies are also common and operate on the principles as lower frequency counters. Often, they have more range before they overflow, for very high frequencies, many designs use a high-speed prescaler to bring the signal frequency down to a point where normal digital circuitry can operate. The displays on such instruments take this into account so they still display the correct value, microwave frequency counters can currently measure frequencies up to almost 56 GHz. The accuracy of a counter is strongly dependent on the stability of its timebase. A timebase is very delicate like the hands of a watch and this can make a frequency reading, when referenced to the timebase, seem higher or lower than the actual value. For higher accuracy measurements, a frequency reference tied to a very high stability oscillator such as a GPS disciplined rubidium oscillator may be used. Where the frequency does not need to be known to such a degree of accuracy. It is also possible to measure using the same techniques in software in an embedded system
11.
Casio 9860 series
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The Casio fx-9860G is a series of graphing calculators manufactured by Casio Computer Co. Ltd, successor of the fx-9750G PLUS/CFX-9850 PLUS/CFX-9950 PLUS/CFX-9970 family of calculators, changes from fx-9750G PLUS, CFX-9850 PLUS, CFX-9950 PLUS, CFX-9970 series include, Increase program capacity to 63000 bytes and storage memory capacity to 1. 5MB. For models with SD suffix, support of Secure Digital memory cards, there are several versions of the fx-9860G, the standard fx-9860G, often referred to as the vanilla flavor, and the SD, AU and Slim versions. The AU version used to limit the amount of flash memory available to 800 Kb to meet Australian school regulations. The SD variant comes with an SD expansion card slot, allowing read, the Slim version has a back-lit display, on-board help, and is designed as a clam-shell to minimize its size. The usual fx-9860G and fx-9860G SD are marketed in France as Graph85 and Graph85 SD, the calculators can be programmed in different ways. The fx-9860Gs come with a built-in BASIC-like interpreter, allowing the user to create simple, the other method is to create an add-in. Add-ins are binary programs, executing directly on the calculators CPU, CASIO has released two official add-ins, GEOMETRY and PHYSIUM. An SDK was released by CASIO in 22/01/2007, allowing users to create their own add-ins, the add-ins and the SDK are available for registered users at CASIOs website. The calculator supports connecting to computer via USB cable, USB connectivity requires installation of USB driver and Program Link software from the bundled CD-ROM. The 3-pin COM port supports transferring data between other CFX-9850/fx-7400 series calculator up to 9600bps, and other fx-9860G series calculator up to 115200bps, the fx-9860GII and fx-9860GII SD became available in May 2009. These calculators have backlit displays and the Geometry and ECON2 apps preinstalled and they also have new mathematical functions. The French versions of the GII models are the Graph 75, the Australian version of the GII is the fx-9860G AU PLUS. Product page Product page Product page
12.
Binary prefix
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A binary prefix is a unit prefix for multiples of units in data processing, data transmission, and digital information, notably the bit and the byte, to indicate multiplication by a power of 2. The computer industry has used the units kilobyte, megabyte, and gigabyte, and the corresponding symbols KB, MB. In citations of main memory capacity, gigabyte customarily means 1073741824 bytes, as this is the third power of 1024, and 1024 is a power of two, this usage is referred to as a binary measurement. In most other contexts, the uses the multipliers kilo, mega, giga, etc. in a manner consistent with their meaning in the International System of Units. For example, a 500 gigabyte hard disk holds 500000000000 bytes, in contrast with the binary prefix usage, this use is described as a decimal prefix, as 1000 is a power of 10. The use of the same unit prefixes with two different meanings has caused confusion, in 2008, the IEC prefixes were incorporated into the ISO/IEC80000 standard. Early computers used one of two addressing methods to access the memory, binary or decimal. For example, the IBM701 used binary and could address 2048 words of 36 bits each, while the IBM702 used decimal, by the mid-1960s, binary addressing had become the standard architecture in most computer designs, and main memory sizes were most commonly powers of two. Early computer system documentation would specify the size with an exact number such as 4096,8192. These are all powers of two, and furthermore are small multiples of 210, or 1024, as storage capacities increased, several different methods were developed to abbreviate these quantities. The method most commonly used today uses prefixes such as kilo, mega, giga, and corresponding symbols K, M, and G, the prefixes kilo- and mega-, meaning 1000 and 1000000 respectively, were commonly used in the electronics industry before World War II. Along with giga- or G-, meaning 1000000000, they are now known as SI prefixes after the International System of Units, introduced in 1960 to formalize aspects of the metric system. The International System of Units does not define units for digital information and this usage is not consistent with the SI. Compliance with the SI requires that the prefixes take their 1000-based meaning, the use of K in the binary sense as in a 32K core meaning 32 ×1024 words, i. e.32768 words, can be found as early as 1959. Gene Amdahls seminal 1964 article on IBM System/360 used 1K to mean 1024 and this style was used by other computer vendors, the CDC7600 System Description made extensive use of K as 1024. Thus the first binary prefix was born, the exact values 32768 words,65536 words and 131072 words would then be described as 32K, 65K and 131K. This style was used from about 1965 to 1975 and these two styles were used loosely around the same time, sometimes by the same company. In discussions of binary-addressed memories, the size was evident from context