It featured a 5-inch display, 64 KB of memory, a modem, and two 5. But the business model is different. Customers pay by the minute for access to Minitel services sites , charged on their phone bills; France Telecom keeps about a third and passes on the rest to the service provider.
As in the later Web, Minitel service providers run their own servers. But they also pay France Telecom a fee to connect to its network. Despite major efforts in the US, Canada, and Europe, similar videotex systems will fizzle outside France. The electric motors housed inside the joints eliminated the need for the chains or tendons used in earlier robots. DD arms were fast and accurate because they minimize friction and backlash. Truong, founder and president of the French company R2E, created the Micral as a replacement for minicomputers in situations that did not require high performance, such as process control and highway toll collection.
In , Truong sold R2E to Bull. Designed by Don Lancaster, the TV Typewriter is an easy-to-build kit that can display alphanumeric information on an ordinary television set. The original design included two memory boards and could generate and store characters as 16 lines of 32 characters.
A cassette tape interface provided supplementary storage for text. The TV Typewriter was used by many small television stations well in the s. Wang was a successful calculator manufacturer, then a successful word processor company. The Wang makes it a successful computer company, too. Wang sold the primarily through Value Added Resellers, who added special software to solve specific customer problems. The first commercially advertised US computer based on a microprocessor the Intel , the Scelbi has 4 KB of internal memory and a cassette tape interface, as well as Teletype and oscilloscope interfaces.
Scelbi aimed the 8H, available both in kit form and fully assembled, at scientific, electronic, and biological applications. In , Scelbi introduced the 8B version with 16 KB of memory for the business market. The Alto is a groundbreaking computer with wide influence on the computer industry. It was based on a graphical user interface using windows, icons, and a mouse, and worked together with other Altos over a local area network.
It could also share files and print out documents on an advanced Xerox laser printer. For its January issue, hobbyist magazine Popular Electronics runs a cover story of a new computer kit — the Altair Within weeks of its appearance, customers inundated its maker, MITS, with orders. Chuck Peddle leads a small team of former Motorola employees to build a low-cost microprocessor.
The and its progeny are still used today, usually in embedded applications. Southwest Technical Products is founded by Daniel Meyer as DEMCO in the s to provide a source for kit versions of projects published in electronics hobbyist magazines. Of the dozens of different SWTP kits available, the proved the most popular. Tailored for online transaction processing, the Tandem is one of the first commercial fault-tolerant computers.
The banking industry rushed to adopt the machine, built to run during repair or expansion. The Video Display Module VDM marks the first implementation of a memory-mapped alphanumeric video display for personal computers.
Introduced at the Altair Convention in Albuquerque in March , the visual display module enabled the use of personal computers for interactive games.
The fastest machine of its day, The Cray-1's speed comes partly from its shape, a "C," which reduces the length of wires and thus the time signals need to travel across them. High packaging density of integrated circuits and a novel Freon cooling system also contributed to its speed.
Typical applications included US national defense work, including the design and simulation of nuclear weapons, and weather forecasting. Intel and Zilog introduced new microprocessors. Five times faster than its predecessor, the , the Intel could address four times as many bytes for a total of 64 kilobytes. The Zilog Z could run any program written for the and included twice as many built-in machine instructions. Designed by Sunnyvale, California native Steve Wozniak, and marketed by his friend Steve Jobs, the Apple-1 is a single-board computer for hobbyists.
With an order for 50 assembled systems from Mountain View, California computer store The Byte Shop in hand, the pair started a new company, naming it Apple Computer, Inc.
In all, about of the boards were sold before Apple announced the follow-on Apple II a year later as a ready-to-use computer for consumers, a model which sold in the millions for nearly two decades. When connected to a color television set, the Apple II produced brilliant color graphics for the time. Millions of Apple IIs were sold between and , making it one of the longest-lived lines of personal computers. Apple gave away thousands of Apple IIs to school, giving a new generation their first access to personal computers.
The TRS proved popular with schools, as well as for home use. The TRS line of computers later included color, portable, and handheld versions before being discontinued in the early s. The first of several personal computers released in , the PET comes fully assembled with either 4 or 8 KB of memory, a built-in cassette tape drive, and a membrane keyboard.
The PET was popular with schools and for use as a home computer. After the success of the PET, Commodore remained a major player in the personal computer market into the s. The success of the VAX family of computers transformed DEC into the second-largest computer company in the world, as VAX systems became the de facto standard computing system for industry, the sciences, engineering, and research. Shortly after delivery of the Atari VCS game console, Atari designs two microcomputers with game capabilities: the Model and Model The served primarily as a game console, while the was more of a home computer.
Atari's 8-bit computers were influential in the arts, especially in the emerging DemoScene culture of the s and '90s. The Motorola microprocessor exhibited a processing speed far greater than its contemporaries. This high performance processor found its place in powerful work stations intended for graphics-intensive programs common in engineering.
Intended to be a less expensive alternative to the PET, the VIC was highly successful, becoming the first computer to sell more than a million units.
Commodore even used Star Trek television star William Shatner in advertisements. About 50, were sold in Britain, primarily to hobbyists, and initially there was a long waiting list for the system.
The machine was expandable, with ports for cassette storage, serial interface and rudimentary networking. The DN is based on the Motorola microprocessor, high-resolution display and built-in networking - the three basic features of all workstations.
Apollo and its main competitor, Sun Microsystems, optimized their machines to run the computer-intensive graphics programs common in engineering and scientific applications. Apollo was a leading innovator in the workstation field for more than a decade, and was acquired by Hewlett-Packard in IBM's brand recognition, along with a massive marketing campaign, ignites the fast growth of the personal computer market with the announcement of its own personal computer PC.
It featured a 5-inch display, 64 KB of memory, a modem, and two 5. Thousands of software titles were released over the lifespan of the C64 and by the time it was discontinued in , it had sold more than 22 million units.
It is recognized by the Guinness Book of World Records as the greatest selling single computer of all time. Franklin was able to undercut Apple's pricing even while offering some features not available on the original.
Sun Microsystems grows out of this prototype. Sun helped cement the model of a workstation having an Ethernet interface as well as high-resolution graphics and the UNIX operating system. Lisa is the first commercial personal computer with a graphical user interface GUI.
It was thus an important milestone in computing as soon Microsoft Windows and the Apple Macintosh would soon adopt the GUI as their user interface, making it the new paradigm for personal computing.
The success of the Portable inspired many other early IBM-compatible computers. Compaq's success launched a market for IBM-compatible computers that by had achieved an percent share of the personal computer market.
The Macintosh was the first successful mouse-driven computer with a graphical user interface and was based on the Motorola microprocessor.
The PC Jr. While the PC Jr. It also included more memory and accommodated high-density 1. By the early s, Dell became one of the leading computer retailers. It developed a very loyal following while add-on components allowed it to be upgraded easily.
The inside of the Amiga case is engraved with the signatures of the Amiga designers, including Jay Miner as well as the paw print of his dog Mitchy. At 4 million operations per second and 4 kilobytes of memory, the gave PCs as much speed and power as older mainframes and minicomputers. The chip brought with it the introduction of a bit architecture, a significant improvement over the bit architecture of previous microprocessors.
It had two operating modes, one that mirrored the segmented memory of older x86 chips, allowing full backward compatibility, and one that took full advantage of its more advanced technology. It performed 2 million instructions per second, but other RISC-based computers worked significantly faster.
Daniel Hillis of Thinking Machines Corporation moves artificial intelligence a step forward when he develops the controversial concept of massive parallelism in the Connection Machine CM The machine used up to 65, one-bit processors and could complete several billion operations per second. Each processor had its own small memory linked with others through a flexible network that users altered by reprogramming rather than rewiring.
Using this system, the machine could work faster than any other at the time on a problem that could be parceled out among the many processors. One of Britain's leading computer companies, Acorn continued the Archimedes line, which grew to nearly twenty different models, into the s. The computer he created, an all-black cube was an important innovation.
This object-oriented multitasking operating system was groundbreaking in its ability to foster rapid development of software applications.
VTech, founded in Hong Kong, had been a manufacturer of Pong-like games and educational toys when they introduce the Laser computer. The RISC microprocessor had a bit integer arithmetic and logic unit the part of the CPU that performs operations such as addition and subtraction , a bit floating-point unit, and a clock rate of 33 MHz.
The chips remained similar in structure to their predecessors, the chips. What set the apart was its optimized instruction set, with an on-chip unified instruction and data cache and an optional on-chip floating-point unit. Combined with an enhanced bus interface unit, the microprocessor doubled the performance of the without increasing the clock rate. Apple had initially included a handle in their Macintosh computers to encourage users to take their Macs on the go, though not until five years after the initial introduction does Apple introduce a true portable computer.
Sales were weaker than projected, despite being widely praised by the press for its active matrix display, removable trackball, and high performance. The line was discontinued less than two years later. It would serve as the model for several other significant multi-processor systems that would be among the fastest in the world. Based on Charles Babbage's second design for a mechanical calculating engine, a team at the Science Museum in London sets out to prove that the design would have worked as planned.
Apple's Macintosh Portable meets with little success in the marketplace and leads to a complete redesign of Apple's line of portable computers. All three PowerBooks introduced featured a built-in trackball, internal floppy drive, and palm rests, which would eventually become typical of s laptop design.
The PowerBook was the entry-level machine, while the PowerBook was more powerful and had a larger memory. The PowerBook was the high-end model, featuring an active matrix display, faster processor, as well as a floating point unit. The PowerBook line of computers was discontinued in Based on the Touchstone Delta computer Intel had built at Caltech, the Paragon is a parallel supercomputer that uses 2, later increased to more than four thousand Intel i processors.
More than one hundred Paragons were installed over the lifetime of the system, each costing as much as five million dollars. The Paragon at Caltech was named the fastest supercomputer in the world in Paragon systems were used in many scientific areas, including atmospheric and oceanic flow studies, and energy research.
Apple enters the handheld computer market with the Newton. The handwriting recognition software was much maligned for inaccuracy. The Newton line never performed as well as hoped and was discontinued in The Pentium introduced several advances that made programs run faster such as the ability to execute several instructions at the same time and support for graphics and music.
Disk drives, which provide mass storage, are connected to the motherboard with one cable, and to the power supply through another cable. Usually, disk drives are mounted in the same case as the motherboard; expansion chassis are also made for additional disk storage. For extended amounts of data, a tape drive can be used or extra hard disks can be put together in an external case. Capabilities of the personal computers hardware can sometimes be extended by the addition of expansion cards connected via an expansion bus.
A computer case is an enclosure that contains the main components of a computer. They are usually constructed from steel or aluminum combined with plastic, although other materials such as wood have been used. Cases are available in different sizes and shapes; the size and shape of a computer case is usually determined by the configuration of the motherboard that it is designed to accommodate, since this is the largest and most central component of most computers.
The most popular style for desktop computers is ATX, although microATX and similar layouts became very popular for a variety of uses. Companies like Shuttle Inc. This protects against overloading the supply, and guards against performance degradation.
The central processing unit, or CPU, is a part of a computer that executes instructions of a software program. In newer PCs, the CPU contains over a million transistors in one integrated circuit chip called the microprocessor.
In most cases, the microprocessor plugs directly into the motherboard. The chip generates so much heat that the PC builder is required to attach a special cooling device to its surface; thus, modern CPUs are equipped with a fanattached via heat sink. The motherboard, also referred to as system board or main board, is the primary circuit board within a personal computer, and other major system components plug directly into it or via a cable.
Often a motherboard will also contain one or more peripheral buses and physical connectors for expansion purposes. Sometimes a secondary daughter board is connected to the motherboard to provide further expandability or to satisfy space constraints. Main memory is much faster than mass storage devices like hard disk drives or optical discs, but is usually volatile, meaning that it does not retain its contents instructions or data in the absence of power, and is much more expensive for a given capacity than is most mass storage.
As a result, main memory is generally not suitable for long-term or archival data storage. Mass storage devices store programs and data even when the power is off; they do require power to perform read and write functions during usage. Although flash memory has dropped in cost, the prevailing form of mass storage in personal computers is still the hard disk drive. If the mass storage controller provides additional ports for expandability, a PC may also be upgraded by the addition of extra hard disk or optical disc drives.
Solid state drives SSDs are a much faster but also a much more expensive replacement for traditional mechanical hard disk drives. A visual display unit, computer monitor or just display, is a piece of electrical equipment, usually separate from the computer case, which displays visual images without producing a permanent computer record.
Multi-monitor setups are also quite common. The display unit houses an electronic circuitry that generates its picture from signals received from the computer. The images from computer monitors originally contained only text, but as graphical user interfaces emerged and became common, they began to display more images and multimedia content. The video card—otherwise called a graphics card, graphics adapter or video adapter—processes the graphics output from the motherboard and transmits it to the display.
It is an essential part of modern multimedia-enriched computing. On older models, and today on budget models, graphics circuitry may be integrated with the motherboard, but for modern and flexible machines, they are connected by the PCI, AGP, or PCI Express interface. When the IBM PC was introduced, most existing business-oriented personal computers used text-only display adapters and had no graphics capability.
Home computers at that time had graphics compatible with television signals, but with low resolution by modern standards owing to the limited memory available to the eight-bit processors available at the time. A keyboard is an arrangement of buttons that each correspond to a function, letter, or number. They are the primary devices used for inputting text. In most cases, they contain an array of keys specifically organized with the corresponding letters, numbers, and functions printed or engraved on the button.
They are generally designed around an operators language, and many different versions for different languages exist. They have evolved over time, and have been modified for use in computers with the addition of function keys, number keys, arrow keys, and keys specific to an operating system. Often, specific functions can be achieved by pressing multiple keys at once or in succession, such as inputting characters with accents or opening a task manager.
Programs use keyboard shortcuts very differently and all use different keyboard shortcuts for different program specific operations, such as refreshing a web page in a web browser or selecting all text in a word processor.
A computer mouse is a small handheld device that users hold and slide across a flat surface, pointing at various elements of a graphical user interface with an on-screen cursor, and selecting and moving objects using the mouse buttons. The scroll wheel can also be pressed down, and therefore be used as a third button.
Some mouse wheels may be tilted from side to side to allow sideways scrolling. Different programs make use of these functions differently, and may scroll horizontally by default with the scroll wheel, open different menus with different buttons, etc. These functions may be also user-defined through software utilities. However, these systems were subject to low durability, accuracy and required internal cleaning.
Modern mice use optical technology to directly trace movement of the surface under the mouse and are much more accurate, durable and almost maintenance free. They work on a wider variety of surfaces and can even operate on walls, ceilings or other non-horizontal surfaces. A proper ergonomic design of a personal computer workplace is necessary to prevent repetitive strain injuries, which can develop over time and can lead to long-term disability.
All computers require either fixed or removable storage for their operating system, programs and user-generated material. Early home computers used compact audio cassettes for file storage; these were at the time a very low cost storage solution, but were displaced by floppy disk drives when manufacturing costs dropped, by the mids.
Initially, the 5. As memory sizes increased, the capacity of the floppy did not keep pace; the Zip drive and other higher-capacity removable media were introduced but never became as prevalent as the floppy drive. By the late s, the optical drive, in CD and later DVD and Blu-ray Disc forms, became the main method for software distribution, and writeable media provided means for data backup and file interchange.
As a result, floppy drives became uncommon in desktop personal computers since about , and were dropped from many laptop systems even earlier.
The NeXT computer introduced in did not include a floppy drive, which at the time was unusual. A second generation of tape recorders was provided when videocassette recorders were pressed into service as backup media for larger disk drives. All these systems were less reliable and slower than purpose-built magnetic tape drives. Such tape drives were uncommon in consumer-type personal computers but were a necessity in business or industrial use. Interchange of data such as photographs from digital cameras is greatly expedited by installation of a card reader, which is often compatible with several forms of flash memory devices.
It is usually faster and more convenient to move large amounts of data by removing the card from the mobile device, instead of communicating with the mobile device through a USB interface. A USB flash drive performs much of the data transfer and backup functions formerly done with floppy drives, Zip disksand other devices.
Mainstream operating systems for personal computers provide built-in support for USB flash drives, allowing interchange even between computers with different processors and operating systems.
The compact size and lack of moving parts or dirt-sensitive media, combined with low cost and high capacity, have made USB flash drives a popular and useful accessory for any personal computer user.
The operating system can be located on any storage, but is typically installed on a hard disk or solid-state drive. While this is slow compared to storing the operating system on a hard disk drive, it is typically used for installation of operating systems, demonstrations, system recovery, or other special purposes. Large flash memory is currently more expensive than hard disk drives of similar size as of mid but are starting to appear in laptop computers because of their low weight, small size and low power requirements.
Computer communications involve internal modem cards, modems, network adapter cards, and routers. Common peripherals and adapter cards include headsets, joysticks, microphones, printers, scanners, sound adapter cards as a separate card rather than located on the motherboard , speakers and webcams.
Computer software is any kind of computer program, procedure, or documentation that performs some task on a computer system. Software applications are common for word processing, Internet browsing, Internet faxing, e-mail and other digital messaging, multimedia playback, playing of computer game, and computer programming. The user of a modern personal computer may have significant knowledge of the operating environment and application programs, but is not necessarily interested in programming nor even able to write programs for the computer.
However, the software industry continuously provide a wide range of new products for use in personal computers, targeted at both the expert and the non-expert user. An operating system OS manages computer resources and provides programmers with an interface used to access those resources. An operating system processes system data and user input, and responds by allocating and managing tasks and internal system resources as a service to users and programs of the system.
An operating system performs basic tasks such as controlling and allocating memory, prioritizing system requests, controlling input and outputdevices, facilitating computer networking, and managing files. Windows, OS X, and Linux all have server and personal variants. With the exception of Microsoft Windows, the designs of each of the them were inspired by or directly inherited from the Unix operating system, which was developed at Bell Labs beginning in the late s and spawned the development of numerous free and proprietary operating systems.
Microsoft Windows is the collective brand name of several operating systems made by Microsoft. Linux is a family of Unix-like computer operating systems.
Linux is one of the most prominent examples of free software and open source development: typically all underlying source code can be freely modified, used, and redistributed by anyone. It is used as an operating system for a wide variety of computer hardware, including desktop computers, netbooks, supercomputers, [77] video game systems, such as the PlayStation 3 until this option was removed remotely by Sony in [78] , several arcade games, and embedded devices such as mobile phones,portable media players, routers, and stage lighting systems.
Generally, a computer user uses application software to carry out a specific task. System software supports applications and provides common services such as memory management, network connectivity and device drivers, all of which may be used by applications but are not directly of interest to the end user.
A simplified analogy in the world of hardware would be the relationship of an electric light bulb an application to an electric power generation plant a system : the power plant merely generates electricity, not itself of any real use until harnessed to an application like the electric light that performs a service that benefits the user.
Typical examples of software applications are word processors, spreadsheets, and media players. Multiple applications bundled together as a package are sometimes referred to as an application suite. Microsoft Office and OpenOffice. The separate applications in a suite usually have a user interface that has some commonality making it easier for the user to learn and use each application. Often, they may have some capability to interact with each other in ways beneficial to the user; for example, a spreadsheet might be able to be embedded in a word processor document even though it had been created in the separate spreadsheet application.
User-written software include spreadsheet templates, word processor macros, scientific simulations, graphics and animation scripts; even email filters are a kind of user software. Users create this software themselves and often overlook how important it is. PC gaming is popular among the high-end PC market. Gaming platforms like Steam software and GOG.
Toxic chemicals found in computer hardware include lead, mercury, cadmium, chromium, plastic PVC , and barium. Lead is found in a cathode ray tube CRT display, and on all of the printed circuit boards and most expansion cards. Plastic is found mostly in the housing of the computation and display circuitry.
While daily end-users are not exposed to these toxic elements, the danger arises during the computer recycling process, which involves manually breaking down hardware and leads to the exposure of a measurable amount of lead or mercury. A measurable amount of lead or mercury can easily cause serious brain damage or ruin drinking water supplies. Computer recycling is best handled by the electronic waste e-waste industry, and kept segregated from the general community dump.
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