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114-521: The Macintosh IIx is a personal computer designed, manufactured, and sold by Apple Computer from September 1988 to October 1990. This model was introduced as an update to the original Macintosh II , replacing the 16 MHz Motorola 68020 CPU and 68881 FPU with a 68030 CPU and 68882 FPU running at the same clock speed. The initial price of the IIx was US$ 7,769 (equivalent to $ 20,015 in 2023) or US$ 9,369 (equivalent to $ 24,137 in 2023) for

228-442: A TV set or an appropriately sized computer display , and is often used as a digital photo viewer, music and video player, TV receiver, and digital video recorder. HTPCs are also referred to as media center systems or media servers . The goal is to combine many or all components of a home theater setup into one box. HTPCs can also connect to services providing on-demand movies and TV shows. HTPCs can be purchased pre-configured with

342-401: A kit form and in limited volumes, and were of interest mostly to hobbyists and technicians. Minimal programming was done with toggle switches to enter instructions, and output was provided by front panel lamps. Practical use required adding peripherals such as keyboards, computer displays , disk drives , and printers . Micral N was the earliest commercial, non-kit microcomputer based on

456-511: A multitasking operating system . Eventually, due to the influence of the IBM PC on the personal computer market , personal computers and home computers lost any technical distinction. Business computers acquired color graphics capability and sound, and home computers and game systems users used the same processors and operating systems as office workers. Mass-market computers had graphics capabilities and memory comparable to dedicated workstations of

570-553: A portable computer prototype called SCAMP (Special Computer APL Machine Portable) based on the IBM PALM processor with a Philips compact cassette drive, small CRT , and full function keyboard. SCAMP emulated an IBM 1130 minicomputer in order to run APL/1130. In 1973, APL was generally available only on mainframe computers, and most desktop sized microcomputers such as the Wang 2200 or HP 9800 offered only BASIC . Because SCAMP

684-469: A touchscreen display, which can be controlled using either a stylus pen or finger. Some tablets may use a hybrid or convertible design, offering a keyboard that can either be removed as an attachment, or a screen that can be rotated and folded directly over top the keyboard. Some tablets may use desktop-PC operating system such as Windows or Linux, or may run an operating system designed primarily for tablets. Many tablet computers have USB ports, to which

798-835: A 4096-color palette, stereo sound, Motorola 68000 CPU, 256 KB RAM, and 880 KB 3.5-inch disk drive, for US$ 1,295. IBM's first PC was introduced on 12 August 1981 setting what became a mass market standard for PC architecture. In 1982 The Computer was named Machine of the Year by Time magazine. Somewhat larger and more expensive systems were aimed at office and small business use. These often featured 80-column text displays but might not have had graphics or sound capabilities. These microprocessor-based systems were still less costly than time-shared mainframes or minicomputers. Workstations were characterized by high-performance processors and graphics displays, with large-capacity local disk storage, networking capability, and running under

912-518: A book on the six female ENIAC programmers in 2022. These early programmers were drawn from a group of about two hundred women employed as computers at the Moore School of Electrical Engineering at the University of Pennsylvania. The job of computers was to produce the numeric result of mathematical formulas needed for a scientific study, or an engineering project. They usually did so with

1026-410: A computer that could fit on a desk was remarkably small, leading to the desktop nomenclature. More recently, the phrase usually indicates a particular style of computer case . Desktop computers come in a variety of styles ranging from large vertical tower cases to small models which can be tucked behind or rest directly beneath (and support) LCD monitors . While the term desktop often refers to

1140-557: A computer with a vertically aligned computer tower case , these varieties often rest on the ground or underneath desks. Despite this seeming contradiction, the term desktop does typically refer to these vertical tower cases as well as the horizontally aligned models which are designed to literally rest on top of desks and are therefore more appropriate to the desktop term, although both types qualify for this desktop label in most practical situations aside from certain physical arrangement differences. Both styles of these computer cases hold

1254-510: A desk, including a keyboard, a small one-line display, and printer. The Wang 2200 microcomputer of 1973 had a full-size cathode ray tube (CRT) and cassette tape storage. These were generally expensive specialized computers sold for business or scientific uses. 1974 saw the introduction of what is considered by many to be the first true personal computer, the Altair 8800 created by Micro Instrumentation and Telemetry Systems (MITS) . Based on

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1368-468: A factor of five. In July 1953, a 100-word expansion core memory was added to the system, using binary-coded decimal , excess-3 number representation. To support this expansion memory, ENIAC was equipped with a new Function Table selector, a memory address selector, pulse-shaping circuits, and three new orders were added to the programming mechanism. Mechanical computing machines have been around since Archimedes ' time (see: Antikythera mechanism ), but

1482-477: A failure was 116 hours—close to five days. ENIAC could be programmed to perform complex sequences of operations, including loops, branches, and subroutines. However, instead of the stored-program computers that exist today, ENIAC was just a large collection of arithmetic machines, which originally had programs set up into the machine by a combination of plugboard wiring and three portable function tables (containing 1,200 ten-way switches each). The task of taking

1596-415: A few years before. Even local area networking, originally a way to allow business computers to share expensive mass storage and peripherals, became a standard feature of personal computers used at home. An increasingly important set of uses for personal computers relied on the ability of the computer to communicate with other computer systems, allowing interchange of information. Experimental public access to

1710-432: A graphics card installed. For this reason, desktop computers are usually preferred over laptops for gaming purposes. Unlike desktop computers, only minor internal upgrades (such as memory and hard disk drive) are feasible owing to the limited space and power available. Laptops have the same input and output ports as desktops, for connecting to external displays, mice, cameras, storage devices and keyboards. Laptops are also

1824-476: A hardware specification called Handheld PC was later released by Microsoft that run the Windows CE operating system. ENIAC ENIAC ( / ˈ ɛ n i æ k / ; Electronic Numerical Integrator and Computer ) was the first programmable , electronic , general-purpose digital computer , completed in 1945. Other computers had some of these features, but ENIAC was the first to have them all. It

1938-487: A hinged second panel containing a flat display screen. Closing the laptop protects the screen and keyboard during transportation. Laptops generally have a rechargeable battery , enhancing their portability. To save power, weight and space, laptop graphics chips are in many cases integrated into the CPU or chipset and use system RAM, resulting in reduced graphics performance when compared to desktop machines, that more typically have

2052-408: A keyboard or mouse can be connected. Smartphones are often similar to tablet computers , the difference being that smartphones always have cellular integration. They are generally smaller than tablets, and may not have a slate form factor. The ultra-mobile PC (UMPC) is a small tablet computer . It was developed by Microsoft , Intel and Samsung , among others. Current UMPCs typically feature

2166-540: A larger screen or use with video projectors. IBM PC-compatible suitcase format computers became available soon after the introduction of the PC, with the Compaq Portable being a leading example of the type. Later models included a hard drive to give roughly equivalent performance to contemporary desktop computers. The development of thin plasma display and LCD screens permitted a somewhat smaller form factor, called

2280-465: A little more expensive compared to desktops, as the miniaturized components for laptops themselves are expensive. Notebook computers such as the TRS-80 Model 100 and Epson HX-20 had roughly the plan dimensions of a sheet of typing paper ( ANSI A or ISO A4 ). These machines had a keyboard with slightly reduced dimensions compared to a desktop system, and a fixed LCD display screen coplanar with

2394-454: A mechanical adding machine . ENIAC had 20 ten-digit signed accumulators , which used ten's complement representation and could perform 5,000 simple addition or subtraction operations between any of them and a source (e.g., another accumulator or a constant transmitter) per second. It was possible to connect several accumulators to run simultaneously, so the peak speed of operation was potentially much higher, due to parallel operation. It

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2508-412: A mechanical calculator. The women studied the machine's logic, physical structure, operation, and circuitry in order to not only understand the mathematics of computing, but also the machine itself. This was one of the few technical job categories available to women at that time. Betty Holberton (née Snyder) continued on to help write the first generative programming system ( SORT/MERGE ) and help design

2622-739: A microprocessor, the Intel 8008 . It was built starting in 1972, and a few hundred units were sold. This had been preceded by the Datapoint 2200 in 1970, for which the Intel 8008 had been commissioned, though not accepted for use. The CPU design implemented in the Datapoint 2200 became the basis for x86 architecture used in the original IBM PC and its descendants. In 1973, the IBM Los Gatos Scientific Center developed

2736-481: A new naming scheme: devices without an integrated phone are called Windows Mobile Classic instead of Pocket PC, while devices with an integrated phone and a touch screen are called Windows Mobile Professional. Palmtop PCs were miniature pocket-sized computers running DOS that first came about in the late 1980s, typically in a clamshell form factor with a keyboard. Non-x86 based devices were often called palmtop computers, examples being Psion Series 3 . In later years

2850-443: A number to a register, read a number from a register, or add/subtract two numbers. A multiplication of a 10-digit number by a d -digit number (for d up to 10) took d +4 cycles, so the multiplication of a 10-digit number by 10-digit number took 14 cycles, or 2,800 microseconds—a rate of 357 per second. If one of the numbers had fewer than 10 digits, the operation was faster. Division and square roots took 13( d +1) cycles, where d

2964-406: A preview of features that would later become staples of personal computers: e-mail , hypertext , word processing , video conferencing , and the mouse . The demonstration required technical support staff and a mainframe time-sharing computer that were far too costly for individual business use at the time. Early personal computers‍—‌generally called microcomputers‍—‌were often sold in

3078-435: A problem and mapping it onto the machine was complex, and usually took weeks. Due to the complexity of mapping programs onto the machine, programs were only changed after huge numbers of tests of the current program. After the program was figured out on paper, the process of getting the program into ENIAC by manipulating its switches and cables could take days. This was followed by a period of verification and debugging, aided by

3192-558: A series of forty-eight lectures given in Philadelphia, Pennsylvania; all together called The Theory and Techniques for Design of Digital Computers —more often named the Moore School Lectures . Half of these lectures were given by the inventors of ENIAC. ENIAC was a one-of-a-kind design and was never repeated. The freeze on design in 1943 meant that it lacked some innovations that soon became well-developed, notably

3306-615: A shared mainframe computer system was demonstrated as early as 1973 in the Community Memory project, but bulletin board systems and online service providers became more commonly available after 1978. Commercial Internet service providers emerged in the late 1980s, giving public access to the rapidly growing network. In 1991, the World Wide Web was made available for public use. The combination of powerful personal computers with high-resolution graphics and sound, with

3420-482: A special divider/square-rooter unit to perform up to 40 division operations per second or three square root operations per second. The other nine units in ENIAC were the initiating unit (started and stopped the machine), the cycling unit (used for synchronizing the other units), the master programmer (controlled loop sequencing), the reader (controlled an IBM punch-card reader), the printer (controlled an IBM card punch),

3534-423: A technician. During World War II , while the U.S. Army needed to compute ballistics trajectories, many women were interviewed for this task. At least 200 women were hired by the Moore School of Engineering to work as " computers " and six of them were chosen to be the programmers of ENIAC. Betty Holberton , Kay McNulty , Marlyn Wescoff , Ruth Lichterman , Betty Jean Jennings , and Fran Bilas , programmed

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3648-655: A television already in the home as the computer display, with low-detail blocky graphics and a limited color range, and text about 40 characters wide by 25 characters tall. Sinclair Research , a UK company, produced the ZX Series‍—;‌the ZX80 (1980), ZX81 (1981), and the ZX Spectrum ; the latter was introduced in 1982, and totaled 8 million unit sold. Following came the Commodore 64 , totaled 17 million units sold,

3762-424: A ten-digit decimal number in memory. Numbers were passed between these units across several general-purpose buses (or trays , as they were called). In order to achieve its high speed, the panels had to send and receive numbers, compute, save the answer and trigger the next operation, all without any moving parts. Key to its versatility was the ability to branch ; it could trigger different operations, depending on

3876-406: A time, they are commonly connected to a local area network and run multi-user operating systems . Workstations are used for tasks such as computer-aided design , drafting and modeling, computation-intensive scientific and engineering calculations, image processing, architectural modeling, and computer graphics for animation and motion picture visual effects. Before the widespread use of PCs,

3990-601: A wide range of users, not just experienced electronics hobbyists who had the soldering skills to assemble a computer kit. The Apple I as delivered was still technically a kit computer, as it did not have a power supply, case, or keyboard when it was delivered to the Byte Shop. The first successfully mass-marketed personal computer to be announced was the Commodore PET after being revealed in January 1977. However, it

4104-542: Is a desktop computer that generally comprises a high-performance video card , processor and RAM, to improve the speed and responsiveness of demanding video games . An all-in-one computer (also known as single-unit PCs) is a desktop computer that combines the monitor and processor within a single unit. A separate keyboard and mouse are standard input devices, with some monitors including touchscreen capability. The processor and other working components are typically reduced in size relative to standard desktops, located behind

4218-495: Is a portable computer that provides the full capabilities of a desktop computer . Such computers are currently large laptops. This class of computers usually includes more powerful components and a larger display than generally found in smaller portable computers, and may have limited battery capacity or no battery. Netbooks , also called mini notebooks or subnotebooks , were a subgroup of laptops suited for general computing tasks and accessing web-based applications . Initially,

4332-466: 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 manufacturers. Many personal computer users no longer need to write their programs to make any use of a personal computer, although end-user programming is still feasible. This contrasts with mobile systems, where software

4446-400: Is often available only through a manufacturer-supported channel, and end-user program development may be discouraged by lack of support by the manufacturer. Since the early 1990s, Microsoft operating systems (first with MS-DOS and then with Windows ) and Intel hardware – collectively called Wintel – have dominated the personal computer market, and today the term PC normally refers to

4560-499: Is the number of digits in the result (quotient or square root). So a division or square root took up to 143 cycles, or 28,600 microseconds—a rate of 35 per second. (Wilkes 1956:20 states that a division with a 10-digit quotient required 6 milliseconds.) If the result had fewer than ten digits, it was obtained faster. ENIAC was able to process about 500 FLOPS , compared to modern supercomputers' petascale and exascale computing power. ENIAC used common octal-base radio tubes of

4674-536: The Apple I computer circuit board, which was fully prepared and contained about 30 chips. The Apple I computer differed from the other kit-style hobby computers of era. At the request of Paul Terrell , owner of the Byte Shop , Jobs and Wozniak were given their first purchase order, for 50 Apple I computers, only if the computers were assembled and tested and not a kit computer. Terrell wanted to have computers to sell to

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4788-531: The Atanasoff–Berry computer (ABC), prototyped in 1939 by John Atanasoff and Clifford Berry  – U.S. patent 3,120,606 for ENIAC, applied for in 1947 and granted in 1964, was voided by the 1973 decision of the landmark federal court case Honeywell, Inc. v. Sperry Rand Corp. . The decision included: that the ENIAC inventors had derived the subject matter of the electronic digital computer from Atanasoff; gave legal recognition to Atanasoff as

4902-590: The Bendix G15 and LGP-30 of 1956, and the Soviet MIR series of computers developed from 1965 to 1969. By the early 1970s, people in academic or research institutions had the opportunity for single-person use of a computer system in interactive mode for extended durations, although these systems would still have been too expensive to be owned by a single person. The personal computer was made possible by major advances in semiconductor technology. In 1959,

5016-656: The Galaksija (1983) introduced in Yugoslavia and the Amstrad CPC series (464–6128). In the same year, the NEC PC-98 was introduced, which was a very popular personal computer that sold in more than 18 million units. Another famous personal computer, the revolutionary Amiga 1000 , was unveiled by Commodore on 23 July 1985. The Amiga 1000 featured a multitasking, windowing operating system, color graphics with

5130-624: The IBM Personal Computer incorporated the designation into its model name, the term originally described personal computers of any brand. In some contexts, PC is used to contrast with Mac, an Apple Macintosh computer. Since none of these Apple products were mainframes or time-sharing systems, they were all personal computers but not PC (brand) computers. In 1995, a CBS segment on the growing popularity of PC reported: "For many newcomers PC stands for Pain and Confusion." The "brain" [computer] may one day come down to our level [of

5244-405: The lunchbox computer. The screen formed one side of the enclosure, with a detachable keyboard and one or two half-height floppy disk drives, mounted facing the ends of the computer. Some variations included a battery, allowing operation away from AC outlets. A laptop computer is designed for portability with clamshell design, where the keyboard and computer components are on one panel, with

5358-460: The silicon integrated circuit (IC) chip was developed by Robert Noyce at Fairchild Semiconductor , and the metal–oxide–semiconductor (MOS) transistor was developed by Mohamed Atalla and Dawon Kahng at Bell Labs . The MOS integrated circuit was commercialized by RCA in 1964, and then the silicon-gate MOS integrated circuit was developed by Federico Faggin at Fairchild in 1968. Faggin later used silicon-gate MOS technology to develop

5472-661: The "1977 trinity". Mass-market, ready-assembled computers had arrived, and allowed a wider range of people to use computers, focusing more on software applications and less on development of the processor hardware. In 1977 the Heath company introduced personal computer kits known as Heathkits , starting with the Heathkit H8 , followed by the Heathkit H89 in late 1979. With the purchase of the Heathkit H8 you would obtain

5586-766: The 1930s and 1940s are considered the beginning of the modern computer era. ENIAC was, like the IBM Harvard Mark I and the German Z3 , able to run an arbitrary sequence of mathematical operations, but did not read them from a tape. Like the British Colossus , it was programmed by plugboard and switches. ENIAC combined full, Turing-complete programmability with electronic speed. The Atanasoff–Berry Computer (ABC), ENIAC, and Colossus all used thermionic valves (vacuum tubes) . ENIAC's registers performed decimal arithmetic, rather than binary arithmetic like

5700-522: The 1990s Kleiman learned that most of the ENIAC programmers were not invited to the ENIAC’s 50th anniversary event. So she made it her mission to track them down and record their oral histories. The documentary, intended to inspire young women and men to get involved in programming. "They were shocked to be discovered," Kleiman says. "They were thrilled to be recognized, but had mixed impressions about how they felt about being ignored for so long." Kleiman released

5814-555: The 8-bit Intel 8080 Microprocessor, 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 . In 1976, Steve Jobs and Steve Wozniak sold

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5928-708: The Army to fund the project, which put him in charge to oversee it for them. Assembly for the computer began in June 1944. ENIAC was designed by Ursinus College physics professor John Mauchly and J. Presper Eckert of the University of Pennsylvania, U.S. The team of design engineers assisting the development included Robert F. Shaw (function tables), Jeffrey Chuan Chu (divider/square-rooter), Thomas Kite Sharpless (master programmer), Frank Mural (master programmer), Arthur Burks (multiplier), Harry Huskey (reader/printer) and Jack Davis (accumulators). Significant development work

6042-498: The Colossus machines were dismantled in 1945; the remaining two were used to decrypt Soviet messages by GCHQ until the 1960s. The public demonstration for ENIAC was developed by Snyder and Jennings who created a demo that would calculate the trajectory of a missile in 15 seconds, a task that would have taken several weeks for a human computer . For a variety of reasons – including Mauchly's June 1941 examination of

6156-448: The ENIAC to perform calculations for ballistics trajectories electronically for the Army's Ballistic Research Laboratory . While men having the same education and experience were designated as "professionals", these women were unreasonably designated as "subprofessionals", though they had professional degrees in mathematics, and were highly trained mathematicians. These women were not "refrigerator ladies", i.e., models posing in front of

6270-577: The U.S. Army Ordnance Corps in July 1946. It was transferred to Aberdeen Proving Ground in Aberdeen, Maryland in 1947, where it was in continuous operation until 1955. The 1948 Manchester Baby was the first machine to contain all the elements essential to a modern electronic digital computer, as it could be reprogrammed electronically to hold stored programs instead of requiring setting of switches to program as ENIAC did. ENIAC's design and construction

6384-550: The U.S. Army calculate complex ballistics tables. The U.S. Army Ordnance accepted their plan, giving the University of Pennsylvania a six-months research contract for $ 61,700. The construction contract was signed on June 5, 1943; work on the computer began in secret at the University of Pennsylvania 's Moore School of Electrical Engineering the following month, under the code name "Project PX", with John Grist Brainerd as principal investigator. Herman H. Goldstine persuaded

6498-549: The Windows XP, Windows Vista, Windows 7, or Linux operating system , and low-voltage Intel Atom or VIA C7-M processors. A pocket PC is a hardware specification for a handheld-sized computer ( personal digital assistant , PDA) that runs the Microsoft Windows Mobile operating system . It may have the capability to run an alternative operating system like NetBSD or Linux . Pocket PCs have many of

6612-619: The Z3, the ABC and Colossus. Like the Colossus, ENIAC required rewiring to reprogram until April 1948. In June 1948, the Manchester Baby ran its first program and earned the distinction of first electronic stored-program computer . Though the idea of a stored-program computer with combined memory for program and data was conceived during the development of ENIAC, it was not initially implemented in ENIAC because World War II priorities required

6726-473: The ability to be programmed in both APL and BASIC for engineers, analysts, statisticians, and other business problem-solvers. In the late 1960s such a machine would have been nearly as large as two desks and would have weighed about half a ton. Another desktop portable APL machine, the MCM/70 , was demonstrated in 1973 and shipped in 1974. It used the Intel 8008 processor. A seminal step in personal computing

6840-565: The ability to execute the program step by step. A programming tutorial for the modulo function using an ENIAC simulator gives an impression of what a program on the ENIAC looked like. ENIAC's six primary programmers, Kay McNulty , Betty Jennings , Betty Snyder , Marlyn Wescoff , Fran Bilas and Ruth Lichterman , not only determined how to input ENIAC programs, but also developed an understanding of ENIAC's inner workings. The programmers were often able to narrow bugs down to an individual failed tube which could be pointed to for replacement by

6954-584: The ability to store a program. Eckert and Mauchly started work on a new design, to be later called the EDVAC , which would be both simpler and more powerful. In particular, in 1944 Eckert wrote his description of a memory unit (the mercury delay line ) which would hold both the data and the program. John von Neumann, who was consulting for the Moore School on the EDVAC, sat in on the Moore School meetings at which

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7068-477: The capabilities of desktop PCs . Numerous applications are available for handhelds adhering to the Microsoft Pocket PC specification, many of which are freeware . Microsoft-compliant Pocket PCs can also be used with many other add-ons like GPS receivers , barcode readers, RFID readers and cameras. In 2007, with the release of Windows Mobile 6, Microsoft dropped the name Pocket PC in favor of

7182-577: The chassis and CPU card to assemble yourself, additional hardware such as the H8-1 memory board that contained 4k of RAM could also be purchased in order to run software. The Heathkit H11 model was released in 1978 and was one of the first 16-bit personal computers; however, due to its high retail cost of $ 1,295 was discontinued in 1982. During the early 1980s, home computers were further developed for household use, with software for personal productivity, programming and games. They typically could be used with

7296-673: 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. In the history of computing , early experimental machines could be operated by a single attendant. For example, ENIAC which became operational in 1946 could be run by a single, albeit highly trained, person. This mode pre-dated the batch programming, or time-sharing modes with multiple users connected through terminals to mainframe computers. Computers intended for laboratory, instrumentation, or engineering purposes were built, and could be operated by one person in an interactive fashion. Examples include such systems as

7410-420: The constant transmitter, and three function tables. The references by Rojas and Hashagen (or Wilkes) give more details about the times for operations, which differ somewhat from those stated above. The basic machine cycle was 200 microseconds (20 cycles of the 100 kHz clock in the cycling unit), or 5,000 cycles per second for operations on the 10-digit numbers. In one of these cycles, ENIAC could write

7524-407: The construction of a new generation of electronic computing machines, including Electronic Delay Storage Automatic Calculator (EDSAC) at Cambridge University, England and SEAC at the U.S. Bureau of Standards. A number of improvements were made to ENIAC after 1947, including a primitive read-only stored programming mechanism using the function tables as program ROM , after which programming

7638-435: The current (2020) Army supercomputers Jean , Kay , and Betty are named after Jean Bartik (Betty Jennings), Kay McNulty , and Betty Snyder respectively. The "programmer" and "operator" job titles were not originally considered professions suitable for women. The labor shortage created by World War II helped enable the entry of women into the field. However, the field was not viewed as prestigious, and bringing in women

7752-446: The day; the decimal accumulators were made of 6SN7 flip-flops , while 6L7s, 6SJ7s, 6SA7s and 6AC7s were used in logic functions. Numerous 6L6s and 6V6s served as line drivers to drive pulses through cables between rack assemblies. Several tubes burned out almost every day, leaving ENIAC nonfunctional about half the time. Special high-reliability tubes were not available until 1948. Most of these failures, however, occurred during

7866-488: The demonstration were invited to the formal dedication nor to the celebratory dinner held afterwards. The original contract amount was $ 61,700; the final cost was almost $ 500,000 (approximately equivalent to $ 9,000,000 in 2023). It was formally accepted by the U.S. Army Ordnance Corps in July 1946. ENIAC was shut down on November 9, 1946, for a refurbishment and a memory upgrade, and was transferred to Aberdeen Proving Ground , Maryland in 1947. There, on July 29, 1947, it

7980-547: The development of ENIAC. Under Herman and Adele Goldstine 's direction, the computers studied ENIAC's blueprints and physical structure to determine how to manipulate its switches and cables, as programming languages did not yet exist. Though contemporaries considered programming a clerical task and did not publicly recognize the programmers' effect on the successful operation and announcement of ENIAC, McNulty, Jennings, Snyder, Wescoff, Bilas, and Lichterman have since been recognized for their contributions to computing. Three of

8094-400: The electronic speed of computation and the electromechanical speed of input/output, almost any real-world problem was completely I/O bound , even without making use of the original machine's parallelism. Most computations would still be I/O bound, even after the speed reduction imposed by this modification. Early in 1952, a high-speed shifter was added, which improved the speed for shifting by

8208-522: The first commercial electronic computers, the UNIVAC and the BINAC , alongside Jean Jennings. McNulty developed the use of subroutines in order to help increase ENIAC's computational capability. Herman Goldstine selected the programmers, whom he called operators, from the computers who had been calculating ballistics tables with mechanical desk calculators, and a differential analyzer prior to and during

8322-479: The first single-chip microprocessor , the Intel 4004 , in 1971. The first microcomputers , based on microprocessors, were developed during the early 1970s. Widespread commercial availability of microprocessors, from the mid-1970s onwards, made computers cheap enough for small businesses and individuals to own. In what was later to be called the Mother of All Demos , SRI researcher Douglas Engelbart in 1968 gave

8436-461: The girl computers do the work more rapidly and accurately than they would. This is due in large measure to the feeling among the engineers that their college and industrial experience is being wasted and thwarted by mere repetitive calculation." Following the initial six programmers, an expanded team of a hundred scientists was recruited to continue work on the ENIAC. Among these were several women, including Gloria Ruth Gordon . Adele Goldstine wrote

8550-556: The infrastructure provided by the Internet, and the standardization of access methods of the Web browsers , established the foundation for a significant fraction of modern life, from bus time tables through unlimited distribution of free videos through to online user-edited encyclopedias. A workstation is a high-end personal computer designed for technical, mathematical, or scientific applications. Intended primarily to be used by one person at

8664-519: The introduction of the IBM PC, portable computers consisting of a processor, display, disk drives and keyboard, in a suit-case style portable housing, allowed users to bring a computer home from the office or to take notes at a classroom. Examples include the Osborne 1 and Kaypro ; and the Commodore SX-64 . These machines were AC-powered and included a small CRT display screen. The form factor

8778-525: The inventor of the first electronic digital computer; and put the invention of the electronic digital computer in the public domain . The main parts were 40 panels and three portable function tables (named A, B, and C). The layout of the panels was (clockwise, starting with the left wall): An IBM card reader was attached to Constant Transmitter panel 3 and an IBM card punch was attached to Printer Panel 2. The Portable Function Tables could be connected to Function Table 1, 2, and 3. Pieces of ENIAC are held by

8892-549: The keyboard. These displays were usually small, with 8 to 16 lines of text, sometimes only 40 columns line length. However, these machines could operate for extended times on disposable or rechargeable batteries. Although they did not usually include internal disk drives, this form factor often included a modem for telephone communication and often had provisions for external cassette or disk storage. Later, clamshell format laptop computers with similar small plan dimensions were also called notebooks . A desktop replacement computer

9006-687: The last model was the Macintosh IIfx . Apple's nomenclature of the time used the "x" to indicate the presence of the 68030 CPU as used in the Macintosh IIcx and IIvx . Support and spare parts for the IIx were discontinued on August 31, 1998. Personal computer Institutional or corporate computer owners in the 1960s had to write their own programs to do any useful work with computers. While personal computer users may develop their applications, usually these systems run commercial software , free-of-charge software (" freeware "), which

9120-449: The machine for press photography, as then computer scientist undergrad Kathryn Kleiman discovered in her own research as opposed to what she was told by a historian in computing. However, some of the women did not receive recognition for their work on the ENIAC in their entire lifetimes. After the war ended, the women continued to work on the ENIAC. Their expertise made their positions difficult to replace with returning soldiers. Later In

9234-433: The machine to be completed quickly, and ENIAC's 20 storage locations would be too small to hold data and programs. The Z3 and Colossus were developed independently of each other, and of the ABC and ENIAC during World War II. Work on the ABC at Iowa State University was stopped in 1942 after John Atanasoff was called to Washington, D.C. , to do physics research for the U.S. Navy, and it was subsequently dismantled. The Z3

9348-455: The monitor, and configured similarly to laptops. A nettop computer was introduced by Intel in February 2008, characterized by low cost and lean functionality. These were intended to be used with an Internet connection to run Web browsers and Internet applications. A Home theater PC (HTPC) combines the functions of a personal computer and a digital video recorder . It is connected to

9462-491: The original technical description of the ENIAC. Several language systems were developed to describe programs for the ENIAC, including: Although the Ballistic Research Laboratory was the sponsor of ENIAC, one year into this three-year project John von Neumann , a mathematician working on the hydrogen bomb at Los Alamos National Laboratory , became aware of the ENIAC. In December 1945, the ENIAC

9576-503: The primary defining characteristic of netbooks was the lack of an optical disc drive, smaller size, and lower performance than full-size laptops. By mid-2009 netbooks had been offered to users "free of charge", with an extended service contract purchase of a cellular data plan. Ultrabooks and Chromebooks have since filled the gap left by Netbooks. Unlike the generic Netbook name, Ultrabook and Chromebook are technically both specifications by Intel and Google respectively. A tablet uses

9690-409: The public the evening of February 14, 1946, featuring demonstrations of its capabilities. Elizabeth Snyder and Betty Jean Jennings were responsible for developing the demonstration trajectory program, although Herman and Adele Goldstine took credit for it. The machine was formally dedicated the next day at the University of Pennsylvania. None of the women involved in programming the machine or creating

9804-558: The reader from standard IBM cards. The "first production run" of the new coding techniques on the Monte Carlo problem followed in April. After ENIAC's move to Aberdeen, a register panel for memory was also constructed, but it did not work. A small master control unit to turn the machine on and off was also added. The programming of the stored program for ENIAC was done by Betty Jennings, Clippinger, Adele Goldstine and others. It

9918-498: The required hardware and software needed to add television programming to the PC, or can be assembled from components. Keyboard computers are computers inside of keyboards, generally still designed to be connected to an external computer monitor or television . Examples include the Atari ST , Amstrad CPC , BBC Micro , Commodore 64 , MSX , Raspberry Pi 400 , and the ZX Spectrum . The potential utility of portable computers

10032-482: The sign of a computed result. By the end of its operation in 1956, ENIAC contained 18,000 vacuum tubes , 7,200 crystal diodes , 1,500 relays , 70,000 resistors , 10,000 capacitors , and approximately 5,000,000 hand- soldered joints. It weighed more than 30 short tons (27 t), was roughly 8 ft (2 m) tall, 3 ft (1 m) deep, and 100 ft (30 m) long, occupied 300 sq ft (28 m ) and consumed 150 kW of electricity. Input

10146-481: The stored program concept was elaborated. Von Neumann wrote up an incomplete set of notes ( First Draft of a Report on the EDVAC ) which were intended to be used as an internal memorandum—describing, elaborating, and couching in formal logical language the ideas developed in the meetings. ENIAC administrator and security officer Herman Goldstine distributed copies of this First Draft to a number of government and educational institutions, spurring widespread interest in

10260-418: The systems hardware components such as the motherboard , processor chip and other internal operating parts. Desktop computers have an external monitor with a display screen and an external keyboard, which are plugged into ports on the back of the computer case. Desktop computers are popular for home and business computing applications as they leave space on the desk for multiple monitors . A gaming computer

10374-404: The time) to investigate the distance that neutrons would likely travel through various materials. John von Neumann and Stanislaw Ulam realized the speed of ENIAC would allow these calculations to be done much more quickly. The success of this project showed the value of Monte Carlo methods in science. A press conference was held on February 1, 1946, and the completed machine was announced to

10488-572: The ubiquitous Wintel platform. Alternatives to Windows occupy a minority share of the market; these include the Mac platform from Apple (running the macOS operating system), and free and open-source , Unix-like operating systems, such as Linux . Other notable platforms until the 1990s were the Amiga from Commodore , and the PC-98 from NEC . The term PC is an initialism for personal computer. While

10602-449: The version with a 40 MB hard drive. The 800 KB floppy drive was replaced with a 1.44 MB SuperDrive ; the IIx is the first Macintosh to include this as standard. The Mac IIx included 0.25 KiB of L1 instruction CPU cache , 0.25 KiB of L1 data cache, a 16 MHz bus (1:1 with CPU speed), and supported up to System 7.5.5. The IIx was the second of three Macintosh models to use this case allowing dual floppy drives and 6 NuBus slots;

10716-402: The warm-up and cool-down periods, when the tube heaters and cathodes were under the most thermal stress. Engineers reduced ENIAC's tube failures to the more acceptable rate of one tube every two days. According to an interview in 1989 with Eckert, "We had a tube fail about every two days and we could locate the problem within 15 minutes." In 1954, the longest continuous period of operation without

10830-577: Was Turing-complete and able to solve "a large class of numerical problems" through reprogramming. ENIAC was designed by John Mauchly and J. Presper Eckert to calculate artillery firing tables for the United States Army 's Ballistic Research Laboratory (which later became a part of the Army Research Laboratory ). However, its first program was a study of the feasibility of the thermonuclear weapon . ENIAC

10944-408: Was added to ENIAC. ENIAC used ten-position ring counters to store digits; each digit required 36 vacuum tubes, 10 of which were the dual triodes making up the flip-flops of the ring counter. Arithmetic was performed by "counting" pulses with the ring counters and generating carry pulses if the counter "wrapped around", the idea being to electronically emulate the operation of the digit wheels of

11058-508: Was apparent early on. Alan Kay described the Dynabook in 1972, but no hardware was developed. The Xerox NoteTaker was produced in a very small experimental batch around 1978. In 1975, the IBM 5100 could be fit into a transport case, making it a portable computer, but it weighed about 50 pounds. Such early portable computers were termed luggables by journalists owing to their heft. Before

11172-705: Was back-ordered and not available until later that year. Three months later (April), the Apple II (usually referred to as the Apple) was announced with the first units being shipped 10 June 1977, and the TRS-80 from Tandy Corporation / Tandy Radio Shack following in August 1977, which sold over 100,000 units during its lifetime. Together, especially in the North American market, these 3 machines were referred to as

11286-416: Was completed in 1945 and first put to work for practical purposes on December 10, 1945. ENIAC was formally dedicated at the University of Pennsylvania on February 15, 1946, having cost $ 487,000 (equivalent to $ 6,900,000 in 2023), and called a "Giant Brain" by the press. It had a speed on the order of one thousand times faster than that of electro-mechanical machines. ENIAC was formally accepted by

11400-606: Was destroyed by the Allied bombing raids of Berlin in 1943. As the ten Colossus machines were part of the UK's war effort their existence remained secret until the late 1970s, although knowledge of their capabilities remained among their UK staff and invited Americans. ENIAC, by contrast, was put through its paces for the press in 1946, "and captured the world's imagination". Older histories of computing may therefore not be comprehensive in their coverage and analysis of this period. All but two of

11514-411: Was done by graduate students under John Mauchly's supervision. Mauchly began to wonder if electronics could be applied to mathematics for faster calculations. He partnered up with research associate J. Presper Eckert , as Mauchly wasn't an electronics expert, to draft an electronic computer that could work at an excellent pace. In 1942, Mauchly proposed an all-electronic calculating machine that could help

11628-474: Was done by setting the switches. The idea has been worked out in several variants by Richard Clippinger and his group, on the one hand, and the Goldstines, on the other, and it was included in the ENIAC patent . Clippinger consulted with von Neumann on what instruction set to implement. Clippinger had thought of a three-address architecture while von Neumann proposed a one-address architecture because it

11742-565: Was financed by the United States Army, Ordnance Corps, Research and Development Command, led by Major General Gladeon M. Barnes . The total cost was about $ 487,000, equivalent to $ 6,900,000 in 2023. The conception of ENIAC began in 1941, when Friden calculators and differential analyzers were used by the United States Army Ordnance Department to compute firing tables for artillery, which

11856-428: Was first demonstrated as a stored-program computer in April 1948, running a program by Adele Goldstine for John von Neumann. This modification reduced the speed of ENIAC by a factor of 6 and eliminated the ability of parallel computation, but as it also reduced the reprogramming time to hours instead of days, it was considered well worth the loss of performance. Also analysis had shown that due to differences between

11970-401: Was intended to allow these systems to be taken on board an airplane as carry-on baggage, though their high power demand meant that they could not be used in flight. The integrated CRT display made for a relatively heavy package, but these machines were more portable than their contemporary desktop equals. Some models had standard or optional connections to drive an external video monitor, allowing

12084-476: Was possible from an IBM card reader and an IBM card punch was used for output. These cards could be used to produce printed output offline using an IBM accounting machine, such as the IBM 405 . While ENIAC had no system to store memory in its inception, these punch cards could be used for external memory storage. In 1953, a 100- word magnetic-core memory built by the Burroughs Corporation

12198-410: Was possible to wire the carry of one accumulator into another accumulator to perform arithmetic with double the precision, but the accumulator carry circuit timing prevented the wiring of three or more for even higher precision. ENIAC used four of the accumulators (controlled by a special multiplier unit) to perform up to 385 multiplication operations per second; five of the accumulators were controlled by

12312-431: Was simpler to implement. Three digits of one accumulator (#6) were used as the program counter, another accumulator (#15) was used as the main accumulator, a third accumulator (#8) was used as the address pointer for reading data from the function tables, and most of the other accumulators (1–5, 7, 9–14, 17–19) were used for data memory. In March 1948 the converter unit was installed, which made possible programming through

12426-453: Was the 1973 Xerox Alto , developed at Xerox 's Palo Alto Research Center (PARC) . It had a graphical user interface ( GUI ) which later served as inspiration for Apple's Macintosh , and Microsoft's Windows operating system. The Alto was a demonstration project, not commercialized, as the parts were too expensive to be affordable. Also in 1973 Hewlett Packard introduced fully BASIC programmable microcomputers that fit entirely on top of

12540-500: Was the first to emulate APL/1130 performance on a portable, single user computer, PC Magazine in 1983 designated SCAMP a "revolutionary concept" and "the world's first personal computer". This seminal, single user portable computer now resides in the Smithsonian Institution , Washington, D.C.. Successful demonstrations of the 1973 SCAMP prototype led to the IBM 5100 portable microcomputer launched in 1975 with

12654-543: Was turned on and was in continuous operation until 11:45 p.m. on October 2, 1955, when it was retired in favor of the more efficient EDVAC and ORDVAC computers. A few months after ENIAC's unveiling in the summer of 1946, as part of "an extraordinary effort to jump-start research in the field", the Pentagon invited "the top people in electronics and mathematics from the United States and Great Britain" to

12768-588: Was undertaken by the female mathematicians who handled the bulk of the ENIAC programming: Jean Jennings , Marlyn Wescoff , Ruth Lichterman , Betty Snyder , Frances Bilas , and Kay McNulty . In 1946, the researchers resigned from the University of Pennsylvania and formed the Eckert–Mauchly Computer Corporation . ENIAC was a large, modular computer, composed of individual panels to perform different functions. Twenty of these modules were accumulators that could not only add and subtract, but hold

12882-402: Was used to calculate thermonuclear reactions using equations . The data was used to support research on building a hydrogen bomb. Related to ENIAC's role in the hydrogen bomb was its role in the Monte Carlo method becoming popular. Scientists involved in the original nuclear bomb development used massive groups of people doing huge numbers of calculations ("computers" in the terminology of

12996-484: Was viewed as a way to free men up for more skilled labor. Essentially, women were seen as meeting a need in a temporary crisis. For example, the National Advisory Committee for Aeronautics said in 1942, "It is felt that enough greater return is obtained by freeing the engineers from calculating detail to overcome any increased expenses in the computers' salaries. The engineers admit themselves that

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