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Microcomputers
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive (though indeed present-day mainframes such as the IBM System z machines use one or more custom microprocessors as their CPUs). Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense). An early use of the term ''personal computer'' in 1962 predates microprocessor-based designs. ''(See "Personal Computer: Computers at Companies" reference below)''. A ''microcomputer'' used as an embedded control system may have no human-readable inp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micral
Micral is a series of microcomputers produced by the French company Réalisation d'Études Électroniques ( R2E), beginning with the Micral N in early 1973. The Micral N was the first commercially available microprocessor-based computer. In 1986, three judges at The Computer Museum, Boston – Apple II designer and Apple Inc. co-founder Steve Wozniak, early MITS employee and ''PC World'' publisher David Bunnell, and the museum's associate director and curator Oliver Strimpel – awarded the title of "first personal computer using a microprocessor" to the 1973 Micral. The Micral N was the earliest commercial, non-kit personal computer based on a microprocessor (in this case, the Intel 8008). The Computer History Museum currently says that the Micral is one of the earliest commercial, non-kit personal computers. The 1971 |
Minicomputer
A minicomputer, or colloquially mini, is a class of smaller general purpose computers that developed in the mid-1960s and sold at a much lower price than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, ''The New York Times'' suggested a consensus definition of a minicomputer as a machine costing less than (), with an input-output device such as a teleprinter and at least four thousand words of memory, that is capable of running programs in a higher level language, such as Fortran or BASIC. The class formed a distinct group with its own software architectures and operating systems. Minis were designed for control, instrumentation, human interaction, and communication switching as distinct from calculation and record keeping. Many were sold indirectly to original equipment manufacturers (OEMs) for final end use application. During the two decade lifetime of the minicomputer class (1965–1985), almost 100 companies formed and only a hal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Personal Computer
A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or technician. Unlike large, costly minicomputers and mainframes, time-sharing by many people at the same time is not used with personal computers. Primarily in the late 1970s and 1980s, the term home computer was also used. Institutional or corporate computer owners in the 1960s had to write their own programs to do any useful work with the machines. While personal computer users may develop their own applications, usually these systems run commercial software, free-of-charge software (" freeware"), which is most often proprietary, or free and open-source software, which is provided in "ready-to-run", or binary, form. Software for personal computers is typically developed and distributed independently from the hardware or operating system ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altair 8800
The Altair 8800 is a microcomputer designed in 1974 by MITS and based on the Intel 8080 CPU. Interest grew quickly after it was featured on the cover of the January 1975 issue of Popular Electronics and was sold by mail order through advertisements there, in '' Radio-Electronics'', and in other hobbyist magazines. The Altair is widely recognized as the spark that ignited the microcomputer revolution as the first commercially successful personal computer. The computer bus designed for the Altair was to become a ''de facto'' standard in the form of the S-100 bus, and the first programming language for the machine was Microsoft's founding product, Altair BASIC. "This announcement ltair 8800ranks with IBM's announcement of the System/360 a decade earlier as one of the most significant in the history of computing." History While serving at the Air Force Weapons Laboratory at Kirtland Air Force Base, Ed Roberts and Forrest M. Mims III decided to use their electronics background ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
7400 Series
The 7400 series of integrated circuits (ICs) are a popular logic family of transistor–transistor logic (TTL) logic chips. In 1964, Texas Instruments introduced the SN5400 series of logic chips, in a ceramic semiconductor package. A low-cost plastic package SN7400 series was introduced in 1966 which quickly gained over 50% of the logic chip market, and eventually becoming ''de facto'' standardized electronic components. Over the decades, many generations of pin-compatible descendant families evolved to include support for low power CMOS technology, lower supply voltages, and surface mount packages. Overview The 7400 series contains hundreds of devices that provide everything from basic logic gates, flip-flops, and counters, to special purpose bus transceivers and arithmetic logic units (ALU). Specific functions are described in a list of 7400 series integrated circuits. Some TTL logic parts were made with an extended military-specification temperature range. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM PC Compatible
IBM PC compatible computers are similar to the original IBM PC, XT, and AT, all from computer giant IBM, that are able to use the same software and expansion cards. Such computers were referred to as PC clones, IBM clones or IBM PC clones. The term "IBM PC compatible" is now a historical description only, since IBM no longer sells personal computers after it sold its personal computer division in 2005 to Chinese technology company Lenovo. The designation "PC", as used in much of personal computer history, has not meant "personal computer" generally, but rather an x86 computer capable of running the same software that a contemporary IBM PC could. The term was initially in contrast to the variety of home computer systems available in the early 1980s, such as the Apple II, TRS-80, and Commodore 64. Later, the term was primarily used in contrast to Apple's Macintosh computers. These "clones" duplicated almost all the significant features of the original IBM PC architectu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
François Gernelle
François Gernelle (born December 20, 1944) is a French engineer, computer scientist and entrepreneur famous for inventing the first micro-computer using a micro-processor, the Micral N. Education In the late 1960s, Gernelle earned an engineering degree at the Conservatoire National des Arts et Métiers. In 1978, he earned a Ph.D in computer science at the Pierre Mendès-France University of Grenoble. Career Intertechnique and R2E In 1968, he was hired by Intertechnique, a company specialized in electronic measurement for aviation. There he discovered the Intel 8008 microprocessor and imagined all its potential applications. As his hierarchy didn't share his views on the i8008 development capacity, he resigned in 1972 and joined R2E R, or r, is the eighteenth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''ar'' (pronounced ), plural ''ars'', or in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hygrometry
Psychrometrics (or psychrometry, ; also called hygrometry) is the field of engineering concerned with the physical and thermodynamic properties of gas- vapor mixtures. Common applications Although the principles of psychrometry apply to any physical system consisting of gas-vapor mixtures, the most common system of interest is the mixture of water vapor and air, because of its application in heating, ventilation, and air-conditioning and meteorology. In human terms, our thermal comfort is in large part a consequence of not just the temperature of the surrounding air, but (because we cool ourselves via perspiration) the extent to which that air is saturated with water vapor. Many substances are hygroscopic, meaning they attract water, usually in proportion to the relative humidity or above a critical relative humidity. Such substances include cotton, paper, cellulose, other wood products, sugar, calcium oxide (burned lime) and many chemicals and fertilizers. Industries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Magazine Of Fantasy & Science Fiction
''The Magazine of Fantasy & Science Fiction'' (usually referred to as ''F&SF'') is a U.S. fantasy fiction magazine, fantasy and science fiction magazine first published in 1949 by Mystery House, a subsidiary of Lawrence E. Spivak, Lawrence Spivak's Mercury Publications, Mercury Press. Editors Anthony Boucher and J. Francis McComas had approached Spivak in the mid-1940s about creating a fantasy companion to Spivak's existing mystery title, ''Ellery Queen's Mystery Magazine''. The first issue was titled ''The Magazine of Fantasy'', but the decision was quickly made to include science fiction as well as fantasy, and the title was changed correspondingly with the second issue. ''F&SF'' was quite different in presentation from the existing science fiction magazines of the day, most of which were in pulp magazine, pulp format: it had no interior illustrations, no letter column, and text in a single column format, which in the opinion of science fiction historian Mike Ashley (writer), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Byte
The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit of memory in many computer architectures. To disambiguate arbitrarily sized bytes from the common 8-bit definition, network protocol documents such as The Internet Protocol () refer to an 8-bit byte as an octet. Those bits in an octet are usually counted with numbering from 0 to 7 or 7 to 0 depending on the bit endianness. The first bit is number 0, making the eighth bit number 7. The size of the byte has historically been hardware-dependent and no definitive standards existed that mandated the size. Sizes from 1 to 48 bits have been used. The six-bit character code was an often-used implementation in early encoding systems, and computers using six-bit and nine-bit bytes were common in the 1960s. These systems often had memory wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
