Personal Computer 1 Personal Computer
Total Page:16
File Type:pdf, Size:1020Kb
Personal computer 1 Personal computer A personal computer (PC) is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end user, with no intervening computer operator. This is in contrast to the batch processing or time-sharing models which allowed large expensive mainframe systems to be used by many people, usually at the same time, or large data processing systems which required a full-time staff to operate efficiently. A personal computer may be a desktop computer, a laptop, a tablet PC or a handheld PC (also called palmtop). The most common microprocessors in personal computers are x86-compatible CPUs. Software applications for personal computers include word processing, spreadsheets, databases, Web An illustration of a desktop computer browsers and e-mail clients, games, and myriad personal productivity and special-purpose software. Modern personal computers often have high-speed or dial-up connections to the Internet, allowing access to the World Wide Web and a wide range of other resources. A PC may be used at home, or may be found in an office. Personal computers can be connected to a local area network (LAN) either by a cable or a wireless connection. While early PC owners usually had to write their own programs to do anything useful with the machines, today's users have access to a wide range of commercial and non-commercial software which is provided in ready-to-run or ready-to-compile form. Since the 1980s, Microsoft and Intel have dominated much of the personal computer market with the Wintel platform. History In what was later to be called The Mother of All Demos, SRI researcher Douglas Englebart in 1968 gave a preview of what would become the staples of daily working life in the 21st century - 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. 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. Personal computer 2 In the 1970s Hewlett Packard introduced fully BASIC programmable computers that fit entirely on top of a desk, including a keyboard, a small one-line display and printer. The Wang 2200 of 1973 had a full-size CRT and cassette tape storage. The IBM 5100 in 1975 had a small CRT display and could be programmed in BASIC and APL. These were generally expensive specialized computers sold for business or scientific uses. The introduction of the microprocessor, a single chip with all the circuitry that formerly occupied large cabinets, led to the proliferation of personal computers after 1975. HP 9830 was an early desktop computer with printer Early personal computers - generally called microcomputers - were sold often in 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 peripherals such as keyboards, computer terminals, disk drives, and printers. Micral N was the earliest commercial, non-kit "personal" computer based on a microprocessor, the Intel 8008. It was built starting in 1972 and about 90,000 units were sold. Unlike other hobbyist computers of its day, which were sold as electronics kits, in 1976 Steve Jobs and Steve Wozniak sold the Apple I computer circuit board, which was fully prepared and contained about 30 chips. The first complete personal computer was the Commodore PET introduced in January 1977. It was soon followed by the popular Apple II. Mass-market pre-assembled computers allowed a wider range of people to use computers, focusing more on software applications and less on development of the processor hardware. Through the late 1970s and into the 1980s, computers were developed for household use, with software for personal productivity, programming and games. One such machine, the Commodore 64, totaled 17 million units sold, making it the best-selling single personal computer model of all time[1] . Somewhat larger and more expensive systems (although still low-cost compared with minicomputers and mainframes) were aimed at office and small business use. Workstations are characterized by high-performance processors and graphics displays, with large local disk storage, networking capability, and running under 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 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 IBM 5150 as of 1981 personal computers used at home. Personal computer 3 Market and sales In 2001 125 million personal computers were shipped in comparison to 48 thousand in 1977. More than 500 million personal computers were in use in 2002 and one billion personal computers had been sold worldwide since mid-1970s until this time. Of the latter figure, 75 percent were professional or work related, while the rest sold for personal or home use. About 81.5 percent of personal computers shipped had been desktop computers, 16.4 percent laptops and 2.1 percent servers. United States had received 38.8 percent (394 million) of the computers shipped, Europe 25 percent and 11.7 percent had gone to Asia-Pacific region, the fastest-growing market as of 2002. The second billion was expected to be sold by 2008.[2] Almost half of all the households in Western Europe had a personal computer and a computer could be found in 40 percent of homes in United Kingdom, compared with only 13 percent in 1985.[3] The global personal computer shipments were 264 million units in the year 2007, according to iSuppli[4] , up 11.2 percent from 239 million in [5] 2006. In year 2004, the global shipments was 183 million units, Personal computers worldwide in million 11.6 percent increase over 2003.[6] In 2003, 152.6 million computers distinguished by developed and developing world were shipped, at an estimated value of $175 billion.[7] In 2002, 136.7 million PCs were shipped, at an estimated value of $175 billion.[7] In 2000, 140.2 million personal computers were shipped, at an estimated value of $226 billion.[7] Worldwide shipments of personal computers surpassed the 100-million mark in 1999, growing to 113.5 million units from 93.3 million units in 1998.[8] . In 1999, Asia had 14.1 million units shipped.[9] As of June 2008, the number of personal computers in use worldwide hit one billion, while another billion is expected to be reached by 2014. Mature markets like the United States, Western Europe and Japan accounted for 58 percent of the worldwide installed PCs. The emerging markets were expected to double their installed PCs by 2013 and to take 70 percent of the second billion PCs. About 180 million computers (16 percent of the existing installed base) were expected to be replaced and 35 million to be dumped into landfill in 2008. The whole installed base grew 12 percent annually.[10] [11] In the developed world, there has been a vendor tradition to keep adding functions to maintain high prices of personal computers. However, since the introduction of One Laptop per Child foundation and its low-cost XO-1 laptop, the computing industry started to pursue the price too. Although introduced only one year earlier, there were 14 million netbooks sold in 2008.[12] Besides the regular computer manufacturers, companies making especially rugged versions of computers have sprung up, offering alternatives for people operating their machines in extreme weather or environments.[13] Average selling price For Microsoft Windows systems, the average selling price (ASP) showed a decline in 2008/2009, possibly due to low-cost netbooks, drawing $569 for desktop computers and $689 for laptops at U.S. retail in August 2008. In 2009, ASP had further fallen to $533 for desktops and to $602 for notebooks by January and to $540 and $560 in February.[14] According to research firm NPD, average selling price of all Windows portable PCs has fallen from $659 in October 2008 to $519 in October 2009.[15] Personal computer 4 Types Workstation A workstation is a high-end personal computer designed for technical or scientific applications. Intended primarily to be used by one person at 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 modelling, computation-intensive scientific and engineering calculations, image processing, architectural modelling, and computer graphics for animation and motion picture visual effects.[16] Sun SPARCstation 1+, 25 MHz RISC processor from early 1990s Desktop computer Prior to the wide spread of PCs a computer that could fit on a desk was considered remarkably small. Today 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 form factor models that can be tucked behind an LCD monitor. In this sense, the term 'desktop' refers specifically to a horizontally-oriented case, usually intended to have the display screen placed on top to save space on the desk top.