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81-501: The Tesla Personal Supercomputer is a desktop computer ( personal supercomputer ) that is backed by Nvidia and built by various hardware vendors. It is meant to be a demonstration of the capabilities of Nvidia's Tesla GPGPU brand; it utilizes Nvidia's CUDA parallel computing architecture and is powered by up to 2688 parallel processing cores per GPGPU, which allow it to achieve speeds up to 250 times faster than standard PCs, according to Nvidia. This computer hardware article

162-401: A UPS to handle electrical disturbances like short interruptions, blackouts, and spikes; achieving an on-battery time of more than 20–30 minutes for a desktop PC requires a large and expensive UPS. A laptop with a sufficiently charged battery can continue to be used for hours in case of a power outage and is not affected by short power interruptions and blackouts. A desktop computer often has

243-475: A microprocessor as the central processing unit , memory , bus , certain peripherals and other electronic components), disk storage (usually one or more hard disk drives , solid-state drives , optical disc drives , and in early models floppy disk drives ); a keyboard and mouse for input ; and a monitor , speakers , and, often, a printer for output. The case may be oriented horizontally or vertically and placed either underneath, beside, or on top of

324-834: A tower is a form factor of desktop computer case whose height is much greater than its width, thus having the appearance of an upstanding tower block . In computing , a pizza box enclosure is a design for desktop computers. Pizza box cases tend to be wide and flat, resembling pizza delivery boxes and thus the name. Cube Workstations have a cube case enclosure to house the motherboard , PCI-E expansion cards, GPU , CPU , DRAM DIMM slots, computer cooling equipment, chipsets , I / O ports, hard disk drives , and solid-state drives . Gaming computers are desktop computers with high performance CPU , GPU , and RAM optimized for playing video games at high resolution and frame rates . Gaming computer peripheries usually include mechanical keyboards for faster response time, and

405-618: A Mac, with the exception of the even more inexpensive Mac Mini (albeit without a monitor and keyboard), and the MacBooks are the top-selling form factors of the Macintosh platform today. The decades of development mean that most people already own desktop computers that meet their needs and have no need of buying a new one merely to keep pace with advancing technology. Notably, the successive release of new versions of Windows (Windows 95, 98, XP, Vista, 7, 8, 10 and so on) had been drivers for

486-437: A built-in keyboard and a pointing device (such as a touchpad ) for its user and can draw on power supplied by a rechargeable battery. Laptops also commonly integrate wireless technologies like Wi-Fi , Bluetooth , and 3G , giving them a broader range of options for connecting to the internet, though this trend is changing as newer desktop computers come integrated with one or more of these technologies. A desktop computer needs

567-444: A combination of a few symbols. All primitives are defined to have the same precedence , and always associate to the right. Thus, APL is read or best understood from right-to-left . Early APL implementations ( c.  1970 or so) had no programming loop control flow structures, such as do or while loops, and if-then-else constructs. Instead, they used array operations, and use of structured programming constructs

648-549: A decline in sales, in 2018, global PC sales experienced a resurgence, driven by the business market. Desktops remain a solid fixture in the commercial and educational sectors. According to the International Data Corporation (IDC) , PC sales shot up 14.8% between 2020 and 2021 and desktop market grew faster than the laptop market in the second quarter of 2021. Total PC shipments during 2021 reached 348.8 million units, up 14.8% from 2020. This represents

729-503: A dedicated 1 megabyte hard disk. APL gained its foothold on mainframe timesharing systems from the late 1960s through the early 1980s, in part because it would support multiple users on lower-specification systems that had no dynamic address translation hardware. Additional improvements in performance for selected IBM System/370 mainframe systems included the APL Assist Microcode in which some support for APL execution

810-420: A desk. Desktop computers with their cases oriented vertically are referred to as towers . As the majority of cases offered since the mid-1990s are in this form factor, the term desktop has been retronymically used to refer to modern cases offered in the traditional horizontal orientation. Prior to the widespread use of microprocessors , a computer that could fit on a desk was considered remarkably small;

891-463: A fairly large desk, not put on top of it. It was not until the 1970s when fully programmable computers appeared that could fit entirely on top of a desk. 1970 saw the introduction of the Datapoint 2200 , a "smart" computer terminal complete with keyboard and monitor, was designed to connect with a mainframe computer but that did not stop owners from using its built-in computational abilities as

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972-431: A gaming computer mouse which can track higher dots per inch movement. These desktops are connected to home entertainment systems and typically used for amusement purpose. They come with high definition display, video graphics, surround sound and TV tuner systems to complement typical PC features. Over time some traditional desktop computers have been replaced with thin clients utilizing off-site computing solutions like

1053-618: A growth of 33% compared to 2006. In 2008, it was estimated that 145.9 million notebooks were sold and that the number would grow in 2009 to 177.7 million. The third quarter of 2008 was the first time when worldwide notebook PC shipments exceeded desktops, with 38.6 million units versus 38.5 million units. The sales breakdown of the Apple Macintosh has seen sales of desktop Macs staying mostly constant while being surpassed by that of Mac notebooks whose sales rate has grown considerably; seven out of ten Macs sold were laptops in 2009,

1134-461: A new version of the APL language that contained as its primary enhancement the concept of nested arrays , where an array can contain other arrays, and new language features which facilitated integrating nested arrays into program workflow. Ken Iverson, no longer in control of the development of the APL language, left IBM and joined I. P. Sharp Associates , where one of his major contributions was directing

1215-482: A paper published in IBM Systems Journal in 1964. After this was published, the team turned their attention to an implementation of the notation on a computer system. One of the motivations for this focus of implementation was the interest of John L. Lawrence who had new duties with Science Research Associates , an educational company bought by IBM in 1964. Lawrence asked Iverson and his group to help use

1296-570: A ratio projected to rise to three out of four by 2010. The change in sales of form factors is due to the desktop iMac moving from affordable G3 to upscale G4 model and subsequent releases are considered premium all-in-ones. By contrast, the MSRP of the MacBook laptop lines have dropped through successive generations such that the MacBook Air and MacBook Pro constitute the lowest price of entry to

1377-399: A second or third PC in the household that would have performed these tasks, though most families still retain a powerful PC for serious work. Among PC form factors, desktops remain a staple in the enterprise market but lost popularity among home buyers. PC makers and electronics retailers responded by investing their engineering and marketing resources towards laptops (initially netbooks in

1458-692: A selling point for those products. IBM cites its use for problem solving, system design, prototyping, engineering and scientific computations, expert systems, for teaching mathematics and other subjects, visualization and database access. Various implementations of APL by APLX, Dyalog, et al., include extensions for object-oriented programming , support for .NET , XML-array conversion primitives, graphing, operating system interfaces, and lambda calculus expressions. Freeware versions include GNU APL for Linux and NARS2000 for Windows (which also runs on Linux under Wine). Both of these are fairly complete versions of APL2 with various language extensions. APL has formed

1539-617: A server. Thin client computers may do almost all of their computing on a virtual machine in another site. Internal, hosted virtual desktops can offer users a completely consistent experience from anywhere. Workstations are advanced class of personal computers designed for a user and more powerful than a regular PC but less powerful than a server in regular computing. They are capable of high-resolution and three-dimensional interfaces, and typically used to perform scientific and engineering work. Like server computers, they are often connected with other workstations. The main form-factor for this class

1620-500: A set of non- ASCII symbols, which are an extension of traditional arithmetic and algebraic notation. Having single character names for single instruction, multiple data ( SIMD ) vector functions is one way that APL enables compact formulation of algorithms for data transformation such as computing Conway's Game of Life in one line of code. In nearly all versions of APL, it is theoretically possible to express any computable function in one expression, that is, in one line of code. Due to

1701-504: A small CRT display and could be programmed in BASIC and APL . These were generally expensive specialized computers sold for business or scientific uses. Apple II , TRS-80 and Commodore PET were first generation personal home computers launched in 1977, which were aimed at the consumer market – rather than businessmen or computer hobbyists. Byte magazine referred to these three as the "1977 Trinity" of personal computing. Throughout

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1782-564: A special high school course on calculating transcendental functions by series summation. Students tested their code in Hellerman's lab. This implementation of a part of the notation was called Personalized Array Translator (PAT). In 1963, Falkoff, Iverson, and Edward H. Sussenguth Jr. , all working at IBM, used the notation for a formal description of the IBM System/360 series machine architecture and functionality, which resulted in

1863-478: A stand-alone desktop computer. The HP 9800 series , which started out as programmable calculators in 1971 but was programmable in BASIC by 1972, used a smaller version of a minicomputer design based on ROM memory and had small one-line LED alphanumeric displays and displayed graphics with a plotter. The Wang 2200 of 1973 had a full-size cathode-ray tube (CRT) and cassette tape storage. The IBM 5100 in 1975 had

1944-443: A tower case) in order to run these applications, though this has slowed since the late 2000s as the growing popularity of Intel integrated graphics forced game developers to scale back. Creative Technology 's Sound Blaster series were a de facto standard for sound cards in desktop PCs during the 1990s until the early 2000s, when they were reduced to a niche product, as OEM desktop PCs came with sound boards integrated directly onto

2025-431: Is a stub . You can help Misplaced Pages by expanding it . Desktop computer A desktop computer , often abbreviated as desktop , is a personal computer designed for regular use at a stationary location on or near a desk (as opposed to a portable computer ) due to its size and power requirements. The most common configuration has a case that houses the power supply , motherboard (a printed circuit board with

2106-490: Is a Tower case, but most vendors produce compact or all-in-one low-end workstations. Most tower workstations can be converted to a rack-mount version. Oriented for small business class of servers; typically entry-level server machines, with similar to workstation/gaming PC computing powers and with some mainstream servers features, but with only basic graphic abilities; and some desktop servers can be converted to workstations. Desktops have an advantage over laptops in that

2187-450: Is a dyadic operator, the term to its left is required as well. It is surrounded by parentheses since otherwise X would be taken (so that the summation would be of X÷⍴X —each element of X divided by the number of elements in X), and +/X gives the sum of the elements of X. Building on this, the following expression computes standard deviation : Naturally, one would define this expression as

2268-453: Is a notable example of a compact desktop. A laptop without a screen can functionally be used as a compact desktop, sometimes called a "slabtop". An all-in-one (AIO) desktop computer integrates the system's internal components into the same case as the display, thus occupying a smaller footprint (with fewer cables) than desktops that incorporate a tower. The All-in-one systems are rarely labeled as desktop computers. In personal computing ,

2349-443: Is called a workspace . In a workspace the user can define programs and data, i.e., the data values exist also outside the programs, and the user can also manipulate the data without having to define a program. In the examples below, the APL interpreter first types six spaces before awaiting the user's input. Its own output starts in column one. The user can save the workspace with all values, programs, and execution status. APL uses

2430-688: Is compact and terse, APL lends itself well to larger-scale software development and complexity, because the number of lines of code can be reduced greatly. Many APL advocates and practitioners also view standard programming languages such as COBOL and Java as being comparatively tedious. APL is often found where time-to-market is important, such as with trading systems. APL makes a clear distinction between functions and operators . Functions take arrays (variables or constants or expressions) as arguments, and return arrays as results. Operators (similar to higher-order functions ) take functions or arrays as arguments, and derive related functions. For example,

2511-440: Is largely concerned with the design and analysis of explicit procedures for calculating the exact or approximate values of various functions. Such explicit procedures are called algorithms or programs . Because an effective notation for the description of programs exhibits considerable syntactic structure, it is called a programming language . This notation was used inside IBM for short research reports on computer systems, such as

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2592-472: Is quite rare. Compact desktops are reduced in physical proportions compared to full-sized desktops. They are typically small-sized, inexpensive, low-power computers designed for basic tasks such as web browsing , accessing web-based applications , document processing, and audio/video playback. Hardware specifications and processing power are usually reduced and hence make them less appropriate for running complex or resource-intensive applications . A nettop

2673-432: Is specified (as with the statement *3 in APL, or ^3 in other languages), most programming languages one would see this as a syntax error. APL, however, assumes the missing base to be the natural logarithm constant e , and interprets *3 as 2.71828*3 . Suppose that X is an array of numbers. Then (+/X)÷⍴X gives its average. Reading right-to-left , ⍴X gives the number of elements in X, and since ÷

2754-481: Is still most popular on desktops (and laptops), while smartphones (and tablets) use Android or iOS . Towards the middle of the 2010s, media sources began to question the existence of the post-PC trend, at least as conventionally defined, stating that the so-called post-PC devices are just other portable forms of PCs joining traditional desktop PCs which still have their own operation areas and evolve. Although for casual use traditional desktops and laptops have seen

2835-413: Is the grade up character, which had to be made from a delta (shift-H) and a Sheffer stroke (shift-M). This was necessary because the APL character set was much larger than the 88 characters allowed on the typing element, even when letters were restricted to upper-case (capitals). The first APL interactive login and creation of an APL workspace was in 1966 by Larry Breed using an IBM 1050 terminal at

2916-499: Is the default action on any expression for which no action is specified explicitly (e.g. assignment, function parameter). Another example of this theme is that exponentiation in APL is written as 2*3 , which indicates raising 2 to the power 3 (this would be written as 2^3 or 2**3 in some languages, or relegated to a function call such as pow(2, 3); in others). Many languages use * to signify multiplication, as in 2*3 , but APL chooses to use 2×3 . However, if no base

2997-563: The Burroughs B5000 and its stack mechanism when stack machines versus register machines were being evaluated by IBM for upcoming computers. Iverson also used his notation in a draft of the chapter A Programming Language , written for a book he was writing with Fred Brooks , Automatic Data Processing , which would be published in 1963. In 1979, Iverson received the Turing Award for his work on APL. As early as 1962,

3078-485: The IBM System/360 Model 50 computer running in a time-sharing mode and was used internally at IBM. A key development in the ability to use APL effectively, before the wide use of cathode-ray tube (CRT) terminals, was the development of a special IBM Selectric typewriter interchangeable typing element with all the special APL characters on it. This was used on paper printing terminal workstations using

3159-517: The University of Waterloo . In 1976, Bill Gates claimed in his Open Letter to Hobbyists that Microsoft Corporation was implementing APL for the Intel 8080 and Motorola 6800 but had "very little incentive to make [it] available to hobbyists" because of software piracy . It was never released. Starting in the early 1980s, IBM APL development, under the leadership of Jim Brown , implemented

3240-622: The VSAPL program product enjoyed wide use with Conversational Monitor System (CMS), Time Sharing Option (TSO), VSPC , MUSIC/SP , and CICS users. In 1973–1974, Patrick E. Hagerty directed the implementation of the University of Maryland APL interpreter for the 1100 line of the Sperry UNIVAC 1100/2200 series mainframe computers. In 1974, student Alan Stebbens was assigned the task of implementing an internal function. Xerox APL

3321-441: The sum function is derived by applying the reduction operator to the addition function. Applying the same reduction operator to the maximum function (which returns the larger of two numbers) derives a function which returns the largest of a group (vector) of numbers. In the J language, Iverson substituted the terms verb for function and adverb or conjunction for operator . APL also identifies those features built into

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3402-462: The 1980s and 1990s, desktop computers became the predominant type, the most popular being the IBM PC and its clones , followed by the Apple Macintosh , with the third-placed Commodore Amiga having some success in the mid-1980s but declining by the early 1990s. Early personal computers , like the original IBM Personal Computer , were enclosed in a " desktop case ", horizontally oriented to have

3483-695: The APL font has been distinctive, with uppercase italic alphabetic characters and upright numerals and symbols. Most vendors continue to display the APL character set in a custom font. Advocates of APL claim that the examples of so-called write-only code (badly written and almost incomprehensible code) are almost invariably examples of poor programming practice or novice mistakes, which can occur in any language. Advocates also claim that they are far more productive with APL than with more conventional computer languages, and that working software can be implemented in far less time and with far fewer programmers than using other technology. They also may claim that because it

3564-666: The APL implementers' community at Syracuse's Minnowbrook Conference Center in Blue Mountain Lake, New York . In later years, Eugene McDonnell organized similar meetings at the Asilomar Conference Grounds near Monterey , California , and at Pajaro Dunes near Watsonville , California. The SIGAPL special interest group of the Association for Computing Machinery continues to support the APL community. On microcomputers, which became available from

3645-584: The IBM Mohansic Labs near Thomas J. Watson Research Center , the home of APL, in Yorktown Heights , New York. IBM was chiefly responsible for introducing APL to the marketplace. The first publicly available version of APL was released in 1968 for the IBM 1130 . IBM provided APL\1130 for free but without liability or support. It would run in as little as 8k 16-bit words of memory, and used

3726-546: The Selectric typewriter and typing element mechanism, such as the IBM 1050 and IBM 2741 terminal. Keycaps could be placed over the normal keys to show which APL characters would be entered and typed when that key was struck. For the first time, a programmer could type in and see proper APL characters as used in Iverson's notation and not be forced to use awkward English keyword representations of them. Falkoff and Iverson had

3807-677: The advantage over a comparable laptop in computational capacity. Overclocking is often more feasible on a desktop than on a laptop; similarly, hardware add-ons such as discrete graphics co-processors may be possible to install only in a desktop. APL (programming language) A mathematical notation for manipulating arrays was developed by Kenneth E. Iverson , starting in 1957 at Harvard University . In 1960, he began work for IBM where he developed this notation with Adin Falkoff and published it in his book A Programming Language in 1962. The preface states its premise: Applied mathematics

3888-500: The basis of, or influenced, the following languages: APL has been criticized and praised for its choice of a unique, non-standard character set. In the 1960s and 1970s, few terminal devices or even displays could reproduce the APL character set. The most popular ones employed the IBM Selectric print mechanism used with a special APL type element. One of the early APL line terminals (line-mode operation only, not full screen)

3969-401: The case for laptops, though adding or replacing some parts, like the optical drive , hard disk , or adding an extra memory module is often quite simple. This means that a desktop computer configuration, usually a tower case , can be customized and upgraded to a greater extent than laptops. This customization has kept tower cases popular among gamers and enthusiasts . Another advantage of

4050-413: The cloud. As more services and applications are served over the internet from off-site servers, local computing needs decrease, this drives desktop computers to be smaller, cheaper, and need less powerful hardware. More applications and in some cases entire virtual desktops are moved off-site and the desktop computer runs only an operating system or a shell application while the actual content is served from

4131-424: The compact form factors, remain popular for corporate computing environments and kiosks. Some computer cases can be interchangeably positioned either horizontally (desktop) or upright (mini-tower). Influential games such as Doom and Quake during the 1990s had pushed gamers and enthusiasts to frequently upgrade to the latest CPUs and graphics cards ( 3dfx , ATI , and Nvidia ) for their desktops (usually

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4212-750: The desktop is that (apart from environmental concerns ) power consumption is not as critical as in laptop computers because the desktop is exclusively powered from the wall socket. Desktop computers also provide more space for cooling fans and vents to dissipate heat, allowing enthusiasts to overclock with less risk. The two large microprocessor manufacturers, Intel and AMD , have developed special CPUs for mobile computers (i.e. laptops) that consume less power and lower heat, but with lower performance levels. Laptop computers, conversely, offer portability that desktop systems (including small form factor and all-in-one desktops) cannot due to their compact size and clamshell design . The laptop's all-in-one design provides

4293-561: The display screen placed on top, thus saving space on the user's actual desk, although these cases had to be sturdy enough to support the weight of CRT displays that were widespread at the time. Over the course of the 1990s, desktop cases gradually became less common than the more-accessible tower cases that may be located on the floor under or beside a desk rather than on a desk. Not only do these tower cases have more room for expansion, they have also freed up desk space for monitors which were becoming larger every year. Desktop cases, particularly

4374-483: The evolution of Sharp APL to be more in accord with his vision. APL2 was first released for CMS and TSO in 1984. The APL2 Workstation edition (Windows, OS/2 , AIX , Linux , and Solaris ) followed later. As other vendors were busy developing APL interpreters for new hardware, notably Unix -based microcomputers , APL2 was almost always the standard chosen for new APL interpreter developments. Even today, most APL vendors or their users cite APL2 compatibility as

4455-495: The first attempt to use the notation to describe a complete computer system happened after Falkoff discussed with William C. Carter his work to standardize the instruction set for the machines that later became the IBM System/360 family. In 1963, Herbert Hellerman, working at the IBM Systems Research Institute, implemented a part of the notation on an IBM 1620 computer, and it was used by students in

4536-481: The generality of computer science. APL has explicit representations of functions, operators, and syntax, thus providing a basis for the clear and explicit statement of extended facilities in the language, and tools to experiment on them. This displays " Hello, world ": A design theme in APL is to define default actions in some cases that would produce syntax errors in most other programming languages. The 'Hello, world' string constant above displays, because display

4617-467: The highest level of shipments the PC market has seen since 2012. In addition, gaming desktops have seen a global revenue increase of 54% annually. For gaming the global market of gaming desktops, laptops, and monitors is expected to grow to 61.1 million shipments by the end of 2023, up from 42.1 million, with desktops growing from 15.1 million shipments to 19 million. PC gaming as a whole accounts for 28% of

4698-483: The host services, thus they were their own timesharing systems. First introduced for use at IBM in 1966, the APL\360 system was a multi-user interpreter. The ability to programmatically communicate with the operating system for information and setting interpreter system variables was done through special privileged "I-beam" functions, using both monadic and dyadic operations. In 1973, IBM released APL.SV , which

4779-591: The language as a tool to develop and use computers in education. After Lawrence M. Breed and Philip S. Abrams of Stanford University joined the team at IBM Research, they continued their prior work on an implementation programmed in FORTRAN IV for a part of the notation which had been done for the IBM 7090 computer running on the IBSYS operating system. This work was finished in late 1965 and later named IVSYS (for Iverson system). The basis of this implementation

4860-411: The language to make it worthwhile to memorize the symbols, their semantics, keyboard mappings, and many idioms for common tasks. Unlike traditionally structured programming languages, APL code is typically structured as chains of monadic or dyadic functions , and operators acting on arrays . APL has many nonstandard primitives (functions and operators) that are indicated by a single symbol or

4941-457: The language, and represented by a symbol, or a fixed combination of symbols, as primitives . Most primitives are either functions or operators. Coding APL is largely a process of writing non-primitive functions and (in some versions of APL) operators. However a few primitives are considered to be neither functions nor operators, most noticeably assignment. Some words used in APL literature have meanings that differ from those in both mathematics and

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5022-427: The late 2000s, and then the higher-performance Ultrabooks from 2011 onwards), which manufacturers believed had more potential to revive the PC market than desktops. In April 2017, StatCounter declared a "Milestone in technology history and end of an era" with the mobile Android operating system becoming more popular than Windows (the operating system that made desktops dominant over mainframe computers ). Windows

5103-415: The market in 1978 with an APL Interpreter based on a modified version of Digital Equipment Corp and Carnegie Mellon's, which ran on DEC's KI and KL 36-bit machines. CompuServe's APL was available both to its commercial market and the consumer information service. With the advent first of less expensive mainframes such as the IBM 4300 , and later the personal computer, by the mid-1980s, the timesharing industry

5184-562: The mid-1970s onwards, BASIC became the dominant programming language. Nevertheless, some microcomputers provided APL instead – the first being the Intel 8008 -based MCM/70 which was released in 1974 and which was primarily used in education. Another machine of this time was the VideoBrain Family Computer , released in 1977, which was supplied with its dialect of APL called APL/S. The Commodore SuperPET , introduced in 1981, included an APL interpreter developed by

5265-412: The mobile side. The post-PC trend saw a decline in the sales of desktop and laptop PCs. The decline was attributed to increased power and applications of alternative computing devices, namely smartphones and tablet computers. Although most people exclusively use their smartphones and tablets for more basic tasks such as social media and casual gaming , these devices have in many instances replaced

5346-552: The motherboard. While desktops have long been the most common configuration for PCs, by the mid-2000s the growth shifted from desktops to laptops. Notably, while desktops were mainly produced in the United States, laptops had long been produced by contract manufacturers based in Asia, such as Foxconn . This shift led to the closure of the many desktop assembly plants in the United States by 2010. Another trend around this time

5427-502: The replacement of PCs in the 1990s, but this slowed in the 2000s due to the poor reception of Windows Vista over Windows XP. IDC analyst Jay Chou suggested that Windows 8 actually hurt sales of PCs in 2012, as businesses decided to stick with Windows 7 rather than upgrade. Some suggested that Microsoft had acknowledged "implicitly ringing the desktop PC death knell" as Windows 8 offered little upgrade in desktop PC functionality over Windows 7; instead, Windows 8's innovations were mostly on

5508-548: The spare parts and extensions tend to be standardized, resulting in lower prices and greater availability. For example, the size and mounting of the motherboard are standardized into ATX , microATX , BTX or other form factors . Desktops have several standardized expansion slots , like conventional PCI or PCI Express , while laptops tend to have only one mini-PCI slot and one PC Card slot (or ExpressCard slot). Procedures for assembly and disassembly of desktops tend to be simple and standardized as well. This tends not to be

5589-427: The special APL Selectric typing elements, 987 and 988, designed in late 1964, although no APL computer system was available to use them. Iverson cited Falkoff as the inspiration for the idea of using an IBM Selectric typing element for the APL character set. Many APL symbols, even with the APL characters on the Selectric typing element, still had to be typed in by over-striking two extant element characters. An example

5670-583: The total gaming market as of 2017. This is partially due to the increasing affordability of desktop PCs. Full-sized desktops are characterized by separate display and processing components. These components are connected to each other by cables or wireless connections . They often come in a tower form factor. These computers are easy to customize and upgrade per user requirements, e.g. by expansion card . Early extended-size (significantly larger than mainstream ATX case) tower computers sometimes were labeled as " deskside computers ", but currently this naming

5751-414: The type of computers most commonly used were minicomputers , which, despite the name, were rather large and were "mini" only compared to the so-called " big iron ". Early computers, and later the general purpose high throughput " mainframes ", took up the space of a whole room. Minicomputers , on the contrary, generally fit into one or a few refrigerator-sized racks, or, for the few smaller ones, built into

5832-477: The unusual character set , many programmers use special keyboards with APL keytops to write APL code. Although there are various ways to write APL code using only ASCII characters, in practice it is almost never done. (This may be thought to support Iverson's thesis about notation as a tool of thought . ) Most if not all modern implementations use standard keyboard layouts, with special mappings or input method editors to access non-ASCII characters. Historically,

5913-743: The use of input method editors , keyboard mappings, virtual/on-screen APL symbol sets, or easy-reference printed keyboard cards which can frustrate beginners accustomed to other programming languages. With beginners who have no prior experience with other programming languages, a study involving high school students found that typing and using APL characters did not hinder the students in any measurable way. In defense of APL, it requires fewer characters to type, and keyboard mappings become memorized over time. Special APL keyboards are also made and in use today, as are freely downloadable fonts for operating systems such as Microsoft Windows. The reported productivity gains assume that one spends enough time working in

5994-448: Was a continuation of the same product, but which offered shared variables as a means to access facilities outside of the APL system, such as operating system files. In the mid-1970s, the IBM mainframe interpreter was even adapted for use on the IBM 5100 desktop computer, which had a small CRT and an APL keyboard, when most other small computers of the time only offered BASIC . In the 1980s,

6075-723: Was all but gone. Sharp APL was available from IP Sharp Associates, first as a timesharing service in the 1960s, and later as a program product starting around 1979. Sharp APL was an advanced APL implementation with many language extensions, such as packages (the ability to put one or more objects into a single variable), a file system, nested arrays, and shared variables . APL interpreters were available from other mainframe and mini-computer manufacturers also, notably Burroughs , Control Data Corporation (CDC), Data General , Digital Equipment Corporation (DEC), Harris , Hewlett-Packard (HP), Siemens , Xerox and others. Garth Foster of Syracuse University sponsored regular meetings of

6156-517: Was available from June 1975 for Xerox 560 and Sigma 6, 7, and 9 mainframes running CP-V and for Honeywell CP-6 . In the 1960s and 1970s, several timesharing firms arose that sold APL services using modified versions of the IBM APL\360 interpreter. In North America, the better-known ones were IP Sharp Associates , Scientific Time Sharing Corporation (STSC), Time Sharing Resources (TSR), and The Computer Company (TCC). CompuServe also entered

6237-462: Was described in detail by Abrams in a Stanford University Technical Report, "An Interpreter for Iverson Notation" in 1966. The academic aspect of this was formally supervised by Niklaus Wirth . Like Hellerman's PAT system earlier, this implementation omitted the APL character set, but used special English reserved words for functions and operators. The system was later adapted for a time-sharing system and, by November 1966, it had been reprogrammed for

6318-423: Was included in the processor's firmware , as distinct from being implemented entirely by higher-level software. Somewhat later, as suitably performing hardware was finally growing available in the mid- to late-1980s, many users migrated their applications to the personal computer environment. Early IBM APL interpreters for IBM 360 and IBM 370 hardware implemented their own multi-user management instead of relying on

6399-458: Was often unneeded, since an operation could be performed on a full array in one statement. For example, the iota function ( ι ) can replace for-loop iteration : ιN when applied to a scalar positive integer yields a one-dimensional array (vector), 1 2 3 ... N. Later APL implementations generally include comprehensive control structures, so that data structure and program control flow can be clearly and cleanly separated. The APL environment

6480-578: Was the Texas Instruments TI Model 745 ( c.  1977 ) with the full APL character set which featured half and full duplex telecommunications modes, for interacting with an APL time-sharing service or remote mainframe to run a remote computer job, remote job entry (RJE). Over time, with the universal use of high-quality graphic displays, printing devices and Unicode support, the APL character font problem has largely been eliminated. However, entering APL characters requires

6561-449: Was the increasing proportion of inexpensive base-configuration desktops being sold, hurting PC manufacturers such as Dell whose build-to-order customization of desktops relied on upselling added features to buyers. Battery-powered portable computers had just a 2% worldwide market share in 1986. However, laptops have become increasingly popular, both for business and personal use. Around 109 million notebook PCs shipped worldwide in 2007,

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