"Categories of Computers"
MNG 210 I. Introduction to Computers 1 Introduction In 1967, Dr. John Kemeny of Dartmouth College said, "Knowing how to use a computer will be as important as reading and writing." At that time, most people did not believe such a statement could ever be true. Today, the validity of Dr. Kemeny’s prediction is apparent. The number of computer systems has increased dramatically since 1964. Small computer systems called microcomputers or personal computers, have made computing available to almost everyone in society. Given the increasing use and availability of computer systems, the knowledge of using a computer will continue to be an important if not essential skill in the future. Today, we live in an information society where knowledge workers channel their energies to use and provide a variety of computer-based information services. The term "knowledge worker" was coined by Peter Drucker some thirty years ago to describe someone who adds value by processing existing information to create new information which could be used to define and solve problems. Examples of knowledge workers include lawyers, doctors, diplomats, law makers, marketers, software developers, managers, bankers…The knowledge worker’s job function revolves around the use, manipulation, and dissemination of information. As compared to production workers, knowledge workers utilize their intellectual skills to convert their ideas into products, services, or processes. Cyberphobia and Computer Competency If you’ve got cyberphobia, the fear of computers, computer competency is a sure cure. Computer competency will allow you to be an active and effective participant in the emerging information society. By the end of this course you should: 1. Feel comfortable using and operating a computer system. 2. Be able to interact with the computer – i.e., generate input to the computer and interpret output from it. Input is data entered to a computer system for processing. Output is the presentation of the results of processing (for e.g., a printed résumé or a tax return) 3. Be an intelligent consumer of computers and computer equipment, collectively called hardware. Smart computer shoppers usually get what they need, not what salesmen tell them they need. 4. Be an intelligent consumer of software. Software refers to a collective set of instructions, called programs that can be interpreted by a computer. The programs cause the computer to perform desired functions, such as playing Supermario, the generation of graphics, typing a memo, or browsing the World Wide Web for e.g. 5. Be able to make the computer work for you. The computer competent person knows what hardware and software is required to solve various problems. 6. Be conversant in computerese, the language of computers and information technology. 7. Understand the impact of computers on society, now and in the future. 8. Understand the importance of security, and knowing how to protect yourself What is a Computer and what does it do? "What is a computer?" Technically speaking, the computer is any counting device. But in the context of modern technology, we’ll define the computer as an electronic device capable of interpreting and executing programmed commands for input, output, computation and logic operations. The computer’s power derives from its ability to perform the operations mentioned above very quickly, accurately, reliably and its storage capability. MNG 210 I. Introduction to Computers 2 Speed: Computers perform various operations by executing instructions. The speeds at which these operations are performed are measured in milliseconds, microseconds, nanoseconds, and picoseconds (one thousandth, one millionth, one billionth, and one trillionth of a second, respectively). Accuracy: Zero errors. Computers are amazingly accurate. Errors do occur in computer based information systems, but the vast majority of these errors can be traced to a human error – either inputting incorrect data, or creating incorrect programs. (GIGO – Garbage In, Garbage Out) Reliability: Computers are the most reliable workers when it comes to repetitive tasks. No matter how many times you ask a computer to calculate 456789+16739283, it will always give you the same result. Storage: Computers have total and instant recall of data and an extremely high storage capacity. Computers in Society It is virtually impossible to list all the ways in which computers are used today. Let’s take a quick look at some of the many ways in which computers are used in our society. Computers in Business Were the power to computers ever shut off, business and industry would almost instantly grind to a halt. Computers have become so deeply embedded in information processing and communication systems, that almost no activity would be possible without them. Transaction processing. Most business activities involve transactions with suppliers, employees, or customers. Computers can make these transactions possible and allow instantaneous processing of these transactions. Advantages of the use of computers in business are increased productivity, improved decision making and cost reduction in terms of reduced labor and decreased overstocking of inventory. Financial analysis. Financial analysis is performed throughout the company; from top management on down. People can analyze investments, sales, expenses, markets and other aspects of the business using numbers and graphs. Computers in the Home The lines between work, play, and education are beginning to disappear as resources once available only at work or school become available in the home. From the comfort of your home you can research school or work assignments, exchange e-mail, join special interest groups, download files, play games, or make airline reservations. Home shopping and banking are growing areas of computing. You can visit online stores, view electronic catalogs, and do online shopping. Computers in Education Computers are rapidly becoming the most amazing teaching tool ever invented. They can pace instruction differently for each student, animate important concepts, and use interactivity to involve students in the learning process. Educational software has become a major influence at all levels from elementary schools to universities. Elementary schools are using computers to provide children with new and exciting approaches to learning through the use of CAL (computer aided learning) software where the children can learn various subjects through the use of computer educational games that make learning fun. Secondary schools are using computers to deliver multimedia educational programs and MNG 210 I. Introduction to Computers 3 to enable kids to explore the Web for information. At colleges and universities, computers are used to deliver long distance education to students anywhere in the world, and to incorporate interactivity into the material through the use of discussion boards, online evaluation and others. Computers in Entertainment Information technology isn’t limited to the areas where you would most expect to find it, such as business and industry. It’s also being widely used in the entertainment and arts worlds. From making movies like ‘Toy Story’, the first all-digital animated feature film, to modern dance to professional sports, computers are at work. Animation. In earlier days, Bugs Bunny cartoons for example were laboriously hand-drawn in the hundreds of thousands of frames needed for each cartoon, but today, computers are doing much of the repetitious work. In movies, computers are widely used to create special effects. They are also extensively used behind the scenes to edit film during the production process. Music software allows the creation and editing of recorded music. Computers in Science and Engineering Some of the earliest users of information technology were scientists, engineers and mathematicians. In medicine, physicians use computers to understand the human body, to diagnose disorders, to monitor patients and even to assist while performing major surgeries. In an attempt to better understand earthquakes, scientists use computers to gather and plot data. Large computer systems you don’t see Many of your daily activities are actually interactions with computers that you don’t see. Airline reservations. When you call to make an airline reservation, a travel agent enters your request into a terminal that is connected to a mainframe computer. The terminal then displays all the flights available, the times they depart and arrive, and their fares. If you make a reservation, your request is entered into the computer’s database, and a seat is reserved for you. Banking. When you go to a bank and make a transaction such as a withdrawal or a deposit, the teller enters your transaction into the terminal that is connected to a mainframe computer. The computer processes your transaction, updating your account balance and displaying your current account balance on the terminal. When you make a withdrawal from a bank’s automatic teller machine, a computer dispenses the money and charges the withdrawal against your account. Weather forecasting. When you watch or listen to a weather forecast, you are interacting with the output of a massive and powerful system of computers that compile and analyze data from sensors all over the world. Small computers you don’t see Danny Hillis, founder of Thinking Machines, has been quoted as saying, “I went to my first computer conference at the New York Hilton about 30 years ago. When somebody there predicted the market for microprocessors would eventually be in the millions, someone else said, ‘Where are they all going to go? It’s not like you need a computer in every doorknob!’ Years later, I went back to the same hotel. I MNG 210 I. Introduction to Computers 4 noticed the room keys had been replaced by electronic cards you slide into slots on the doors. There was a computer in every doorknob!” These chips, called embedded microprocessors, are widely used in many devices such as watches, calculators, washing machines, microwave ovens, automobiles, TVs, VCRs, TV and VCR remotes, to name just a few. The Information Processing Cycle Computers are capable of performing 5 general activities. These activities comprise the information processing cycle. They are input, processing, output, storage and retrieval, and distribution and communication. Input. During the input stage, you enter information into the computer. The most common input devices are the keyboard, scanner, mouse, microphone, video camera and web camera. The data you input can be text, numbers, images, videos or sounds. Distribution. Data and information can be Processing. Once information is in printed and distributed or directly distributed the computer, it can be processed. from one computer to other computers. Two For example, the computer can popular ways to do so are to send documents as compare, sort, or do arithmetic attachments to e-mail or to post them on a web operations on numbers, or let you edit site. text, images or sounds. Storage. Programs and data that are not Output. To see (or hear) currently being used are normally stored so what the computer has they can be loaded back into the computer at processed, it has to be output any time. Typically, these are stored on to a screen, printer, or disks or tapes of some kind. speakers. Data is required for all computer processing. It refers to the raw facts (numbers and words), given to a computer during the input operation. Information refers to data that has been processed into a form that has meaning and is useful. This can be expressed as: Data + Meaning = Information. For example, consider a typical market survey that requests a sample of the public to answer some questions about a new product. The questionnaires are input to a system, processed (classified - for e.g., according to sex, or age group, computed - for e.g., calculation of totals, averages, statistics) and analyzed. Individually, a completed questionnaire would not tell the company very much, only the views of one consumer. In this case, the individual questionnaires are data. MNG 210 I. Introduction to Computers 5 Once they have been processed, and analyzed, the resulting report is information. This information has meaning to the company. They can use this information to make meaningful decisions regarding the new product. The production of information by processing data on a computer is called information processing or electronic data processing. During the output operation, the information that has been created is put into some form, such as a printed report, that people can use. The information can also be stored in an electronic format for future use. What is Information Technology? The phrase information technology (IT) refers to the input, processing, storage and the delivery of information, and the processes and devices that make all this possible. Information technology is based on: 1. Hardware 2. Software The term hardware is applied to any of the physical equipment in a computer system. Hardware includes not only the computer and devices such as screens and printers, but also all the elements used to tie the systems together. For example, the telephone wires or cables connecting computer systems. The term software refers to instructions or programs that guide the hardware in the performance of its duties. The twin advances of computer technology and communications technology together make up the foundations of information technology. IT has had a significant impact on office technology and office automation. Office Technology Digital copiers, laser printers, and faxing systems are getting faster, cheaper, more sophisticated, and delivering better quality output all the time. What were previously viewed as standalone machines, have now become integral components of the IT infrastructure. Office Automation The most important components of office automation are: Component Use Word Processing Manipulating text, eg., letters and reports Spreadsheets Manipulating numbers, eg., budgeting, sales reports Databases Storing information efficiently, and in a way that makes it more accessible for everyone, eg., a database of customer names and addresses Telephone and Fax For almost instantaneous communication in speech and writing Networks Allowing exchange and sharing of information resources eg., printers, scanners and e-mail MNG 210 I. Introduction to Computers 6 Office automation can affect businesses in various ways: 1. Routine processing: Data can now be processed in larger volumes, at greater speed and with greater accuracy than with manual systems. 2. Less Paper: There might be less paper in the office (but not necessarily so) 3. Management information: Managers are likely to have access to more accurate, reliable and up-to-date information to aid them in decision making 4. Customer service: Office automation can result in better customer service. Customers could be served better and faster if the staff has on-line access to the organization’s data files. 5. Organization structure: PC networks allow organizations to move towards decentralization of authority within the organization by allowing localized data processing while retaining access to centrally-held databases and programs. Digital Technology We are living in a digital world. The evidence is everywhere. For e.g., digital technologies have revolutionized the communications, information processing and television industries. The term "digital" refers to any technology that breaks data or information down into tiny parts, representing each part as a series of zeroes and ones. The baseline of digital technology is a coding system with only two numbers—1 and 0—hence the term binary. Each of these 1’s and 0’s is called a bit (binary digit). In the digital world bits are things; they take up space; they take time to move from one place to another. A collection of bits can be described and counted, much like anything. The most common way to count the bits in a system is by “byte” or eight bits. Almost anything - text, sound, speech, film, graphics, animations, music can be digitized, and whatever can be digitized can be presented on a computer and transmitted over a network. Advantages of using Digital Technology: Rapid access to the information from remote locations. Information in a digital format can be transmitted quickly and cheaply. First, bits—the 1s and 0s that computers understand—are incredibly cheap. Think of the staggering cost of cutting down trees, turning them into paper, writing words down on this paper, flying the paper via airplane across the country, sorting the paper from among thousands of other pieces of paper, loading the paper onto trucks, and paying someone to carry the paper to someone’s door. Think also of the time that such a process takes. A letter sent from Guyana to the U.S. may well take seven to ten days to arrive. Now think of sending a piece of e-mail. Type the mail into your computer, click on a button, and the bits move almost instantaneously and at a cost so low as to be almost nonexistent, to any place on the globe. Information in a digital format can be copied much more accurately without distortion, and manipulated much more easily than analog information which conveys data as electronic signals of varying frequency or amplitude that are added to carrier waves of a given frequency. Broadcast and phone transmission has conventionally used analog technology. Think of the difference in sound quality between an old LP recording and a music CD. The difference is that the former is an analog medium, whereas the latter is digital, and digital materials can be reproduced at any resolution. At some point, the level of resolution achieved by digitizing a MNG 210 I. Introduction to Computers 7 signal, such as a music track or a graphic image, becomes so good that it is indistinguishable from the real thing. Because digital images can be compressed, the amount of digital data that can be sent over a particular communication channel greatly exceeds the amount of analog data that can be sent over the same channel. This is what has made it possible for us to send and receive photographs, music and videos over networks. Digital Convergence For nearly two decades, industry sages have heralded the coming age of converging digital technology. High-technology industries, ranging from computers to wireless communications and consumer electronics, are currently being transformed by a process known as "digital convergence," that is, the trend toward growing interoperability among various products and technologies, and their enhanced ability to exchange information with each other. With digital convergence, we are moving away from stand alone pieces of equipment to integrated systems that can communicate with each other. Convergence is being driven by three underlying trends. The first is proliferation of digital data, which provides a common base for handling diverse types of information – numbers, words, music, pictures, video and more – using the same devices, processing techniques and media. The second is widespread connectivity, which helps bring diverse information together, and extends the value and capabilities of a device beyond its out-of-the-box functionality. The third is continuous advances in technology, from battery life to processor speed. In the days of the first computers, transaction and company data were the first types of information digitized. Then came text, opening the world to word processing, followed by audio CDs and finally video. Having all forms of information in the digital domain has given rise to numerous convergence opportunities. Personal Computers and Entertainment A major area of interest is the merging of the PC and entertainment. There are numerous devices that transmit photos, music and videos from the PC to the home stereo/home theater system. Persons might stream home movies from the PC in their den to their flat-screen television in their living room, or wirelessly access music files from any spot in the house. In 2002, Microsoft introduced the Windows XP Media Center Edition, a Windows version specifically designed for PCs that function as digital media hubs (connecting to TVs and music systems, as well as functioning as storage tanks for music files and photos). This concept uses the Internet as input, the PC as organizer and the home theater as output. Exactly how and where we want to hear, listen and manage all this is evolving. Data and Voice Data used to travel over voice (telephone) networks, starting in the 1960s. Increasingly, voice is traveling over data networks. Billions have been spent by private enterprises and telecom carriers to develop voice over IP (VoIP) networks using the Internet's IP protocol. Voice over IP is a telephone service that uses the Internet as a global telephone network. Starting in the mid-1990s, advertiser- supported, free telephone service from PC to PC or between phones and PCs using the public Internet became popular, especially for international calls. Call quality over the Internet, however, can be erratic because the Internet provides no guarantee of quality of service. However, when an organization has control over its network, quality can be excellent. MNG 210 I. Introduction to Computers 8 Wireless and Handheld There is a convergence of wireless transmission for portable phones and cellphones that enable them to also connect to the LAN if they pick up a Wi-Fi signal in the vicinity. Numerous functions are now combined, such as the cellphone/PDA and cellphone/camera/music player. It bundles up a mobile phone with a digital camera and a music player into a single gadget. Tiny video camcorders also function as still cameras, voice recorders, digital music players, Webcams and even external storage drives. Consider the automobile. Via wireless connections, automobiles will be able to access GPS data to pinpoint a person’s location or to provide street-by-street maps. That sets up a collision of three massive industries. In one corner stands the computer and software business. In another is the consumer-electronics sector. The third camp is the communications industry. All three groups will have a hand in building the digital wonders that are headed our way. Basic Types of Computer Systems Based on Usage 1. General Purpose: Perform a wide variety of processing tasks. These are the most common. 2. Dedicated or Special Purpose: Fundamentally the same as a general purpose, but programmed for a specific purpose. They are used in a variety of consumer products, microwaves, telephones, washing machines, etc. There are 4 major categories of computers: microcomputers (PC), minicomputers, mainframe computers and supercomputers. Computers are generally classified according to their size, speed, processing capabilities and price. SUPERCOMPUTERS Supercomputers are the heavyweights in the computing world. These systems perform heavy calculations using hardware and software that is on the cutting edge of technology. These systems often require special liquid or gas cooling to keep them running, incorporate hundreds or thousands of processors, frequently require a large amount of physical space and a dedicated team of professionals to keep the system running. The thousands of processors are all designed to work in parallel. Only government agencies, the U.S. military and a select few corporations and universities own supercomputers because they are exceedingly expensive. They are used for problems requiring complex calculations. These systems are often custom designed to perform specific types of tasks such as graphics rendering, image enhancement (NASA JPL), or mathematical analysis. Supercomputers push the limits of current computer and electronic circuit design and are frequently so huge that they occupy a whole building or series of rooms. Keep in mind that this is only a general definition, that technology is constantly advancing and that all of this is subject to change. Twenty years ago, a supercomputer was defined as any device capable of performing one million calculations per second or more. Today's desktop computers have the power to MNG 210 I. Introduction to Computers 9 perform billions of operations per second. Supercomputers today claim trillions of calculations per second. MAINFRAMES In the early days of computing, mainframes were huge computers that could fill an entire room or even a whole floor! As the size of computers has diminished while their power has increased, the term mainframe has fallen out of use in favor of enterprise server. You'll still hear the term used, particularly in large companies to describe the huge machines processing millions of transactions every day. Mainframe is an older term used to refer to a large, powerful computer which performs the bulk of the data processing within an organization and is accessed using dumb terminals as the user interface. Dumb terminals are a combination of a monitor with a keyboard. All major processing is done at the main computer system to which the terminal is attached. Mainframe computers can support hundreds or thousands of users, handling massive amounts of input, output, and storage, and processing transactions at a very high rate. Mainframe computers are used in large organizations, typically in a multi-user environment, where many users need access to shared data and programs. For example, in government organizations, banks, universities, research organizations etc. Mainframes are also used as e-commerce servers, handling transactions over the Internet. Mainframes usually require a specialized environment including separate air conditioning and electrical power. Today, most mainframes are general-purpose systems designed to perform any data processing function needed by an organization. Most mainframes are housed in a single data center (one large room). IBM (International Business Machines) and DEC (Digital Equipment Corporation) were two of the bigger mainframe manufacturers. DEC is now a division of Compaq, which is owned by Hewlett-Packard who also toyed with the minicomputer before focusing on printing technologies. MINICOMPUTERS Until the late 1960s, all computers were mainframe computers, and they were expensive – too expensive for all but the larger companies. Large companies shelled out $1.5 million and more for mainframe computers with less power than today’s $500 PCs. In the late 1960s, computer vendors introduced smaller, slightly less powerful computers that were more affordable for smaller companies. The industry dubbed these small computers minicomputers, or simply minis. The term was used until recently, when the distinction between minis and mainframes began to blur. Today the term is seldom used. Smaller mainframes are called mid-range servers now. They are larger than microcomputers. MICROCOMPUTERS Microcomputers are physically the smallest computers and fit on top of or underneath a desk and are MNG 210 I. Introduction to Computers 10 therefore often referred to as desktops, towers or personal computers. They are general-purpose machines and frequently have networking capability. They are also frequently used as stand-alone computers, in contrast to mainframes which are designed specifically for the multiuser environment. Desktop Computers Desktop computers, those used by most individuals, are designed to be permanently positioned on a desk. Workstations are extremely powerful desktop computers with a more powerful processor, additional memory and enhanced capabilities used mainly by scientists, engineers, and people who work with graphics, such as in game development. Portable Computers Notebook (laptop) computers are used by people who need the power of a desktop system, but also portability. They are light weight and can be easily carried around. On the road, they can run on rechargeable battery packs. Common input devices used in laptop computers are the keyboard, and pointing device such as a mouse, trackball or touchpad. Handheld PCs or Palmtops (such as PDAs – Personal Digital Assistant) contain considerable computing power and are small enough to be held in the palm of one hand. They however lack the power of a desktop or notebook PC, but offer features for users who need limited functions and small size. They have very small keyboards, so they cannot be easily used for word processing or other applications that require you to enter a lot of data. However, they can be used in many special applications such as maintaining appointment schedules, storing phone numbers and addresses etc. They often come with a mini operating system, synchronization software (for transferring data between the palmtop and a microcomputer (desktop). They often use flash memory instead of a hard drive for storage. Embedded Systems These are the chips and systems built into your favorite electronics, your house, your car, and even your appliances. Chips and software are embedded in the product to add functions that would otherwise not be possible without them. Today's cars use dozens of embedded computers to control fuel consumption, exhaust emissions, braking, acceleration, climate control and many other basic functions that once were purely mechanical. Houses use embedded chips in the thermostats of the hot water heater, the heating system, microwaves, washing machines, TV remote, in the security system if you have one and many more. EVOLUTION OF THE COMPUTER INDUSTRY Early History The last three decades have been the most exciting part of the short but event-filled history of the electronic computer. The overview of the history of computers that follows will provide you with a historical perspective and a feeling for the ‘roots’ of the modern computer. MNG 210 I. Introduction to Computers 11 MNG 210 I. Introduction to Computers 12 MNG 210 I. Introduction to Computers 13 GENERATIONS OF COMPUTERS The First Generation of Computers (1946 through 1959) Vacuum Tubes. The first generation of computers was characterized by the most prominent feature of the ENIAC - vacuum tubes. Computers based in this technology were very fragile and prone to breakdown. The computer called the Universal Automatic Computer (UNIVAC I) was developed by Mauchly and Eckert for the Remington-Rand Corporation. This was the first commercially available computer. By 1951, other manufacturers, primarily in the punched- card and electronics industries, were beginning to enter the commercial computer market. This group included Burroughs, Honeywell, and International Business Machines (IBM). The Second Generation of Computers (1959 through 1964) Transistors. The invention of Transistors signaled the start of the second generation of computers. The transistor meant more powerful, more reliable and less expensive computers that would occupy less space and give off less heat than did vacuum-tube-powered computers. The cost of a computer during the first, second and part of the third generations represented a significant portion of a company’s budget. Computers were expensive. The Third Generation of Computers (1964 through 1971) Integrated Circuits (IC). These have up to a few thousand transistors on a single chip. What some computer historians consider being the single most important event in the history of computers occurred when IBM announced their System 360 line of computers on April 7, 1964. The system 360 ushered in the third generation of computers. The System 360s and the third- generation computers of Honeywell, NCR, CDC, UNIVAC, Burroughs, GE and other manufacturers made all previously installed computers obsolete. The demand for small computers in business and for scientific applications was so great that several companies manufactured only small computers. These became known as minicomputers. Digital Equipment Corporation (DEC) and Data General Corporation took an early lead in the sale and manufacture of "minis". The Fourth Generation of Computers (1971 - ) Large Scale Integrated (LSI) and Very Large Scale Integrated (VLSI) Circuits. These have hundreds of thousands to millions of transistors on a single chip. The base technology of today’s computers is still the integrated circuit. This is not to say that three decades have passed without any significant innovations. In truth, the computer industry has experienced a mind-boggling succession of advances in the further miniaturization of circuitry, data communications, the design of computer hardware and software and input/output devices. MNG 210 I. Introduction to Computers 14 One of the most significant contributions to the emergence of the fourth generation of computers is the microprocessor. The microprocessor, which can be contained on a single silicon chip, is a product of the microminiaturization of electronic circuitry. The first fully operational microprocessor, sometimes called a “computer on a chip", was invented in 1971. The microprocessor is the processing component of the small, relatively inexpensive but powerful microcomputer. The microcomputer also called a personal computer has made it possible for small businesses and individuals to own computers. THE BIRTH OF THE PERSONAL COMPUTER (PC) A keyboard, video monitor and memory were attached to the microprocessor and the MICROCOMPUTER, also known as the Personal Computer (PC) was born! Its price is low and no computer operator is between the user and the PC. PCs were made possible by 2 technical innovations in the field of microelectronics: the integrated circuit (IC); and the microprocessor. The IC permitted the miniaturization of computer-memory circuits and the microprocessor reduced the size of a computer’s CPU to the size of a single silicon chip. These factors lowered a computer’s price making it affordable to both home and business users. Evolution of the PC The first desk-top size system specifically designed for personal use appeared in 1974; it was offered by MITS. The computer was called Altair, retailed for slightly less than US$ 400. Computing was now made available to individuals and small companies. Altair was designed around the Intel 8080 microprocessors. The first major electronics firm to manufacture and sell personal computers, Tandy Corporation (Radio Shack), introduced its model in 1977. Cassette tape was used to store the information at that time. Around 1975, two young engineers - Stephen Wozniak and Steven Jobs started a new computer manufacturing company named Apple Computers. They introduced inexpensive data storage and color graphics into their microcomputers. Apple Computers went on to become the fastest-growing company in U.S. business history. In 1981, IBM tossed its hat into the personal computer ring with its announcement of the IBM Personal Computer, or IBM PC. By the end of 1982, 835,000 PCs had been sold. Less than four months after IBM introduced the PC, Time Magazine named the computer "man of the year". When software vendors began to orient their products to the IBM PC, many companies began offering IBM-PC compatibles or clones which were somewhat cheaper than the brand name IBM PC, but had the same architecture as IBM PC and could run any software that could run on IBM PC. The term personal computer (PC) is applied to microcomputers whose design is similar to IBM’s first microcomputer. In 1984, Apple Computer introduced the Macintosh desktop computer with a very “friendly” graphical user interface which made computers easy and fun to use. Graphical User Interface (GUI) has changed the interaction between human and computer from a command driven interface to the now familiar WIMP interface – Windows, Icons, Menus, and Pointing Devices. MNG 210 I. Introduction to Computers 15 Microsoft introduced Windows, a GUI for IBM PC compatible computers in 1985; however, Windows did not enjoy widespread acceptance until 1990 with the release of Windows 3.0 The Basic Hookup for your Laptop/Desktop PC MNG 210 I. Introduction to Computers 16 The Four Fundamental Components of a Personal Computer System A computer system has four fundamental components: a) input b) processor c) output, and d) storage These four components together constitute the hardware of the computer. Hardware refers to those components of the computer that you can see and touch – not just from the outside, but inside the system unit as well. a) Data can be entered to a computer system for processing (input) via a keyboard, a microphone (for voice and sound input), or a point and draw device, such as a mouse. b) The processor provides the intelligence for the computer system, performing all computation and logic operations. c) Output (the results of processing) can be routed to a monitor, audio speakers, or a printer. d) Storage of data and software in a computer system is either temporary or permanent. Random access memory (RAM) provides temporary storage of data and programs during processing. Disks and tapes provide permanent storage for data and programs. MNG 210 I. Introduction to Computers 17 Devices like the printer, various permanent storage devices, monitor, scanner, microphone etc. are referred to as peripheral devices. In addition to the hardware, we also have the software. Computers can’t operate without instructions – step by step procedures that tell them what to do and when to do it. These instructions, are called programs or software, and are usually written by specialists called programmers. There are basically two types of software: a) systems software, and b) applications software. Systems software includes the operating system which is probably the most important software on your computer. Without this software your computer is totally useless. A popular operating system on today’s computers is Microsoft’s MS Windows, of which there are different versions. Windows XP is the most recent. Microsoft recently announced that it will call its next-generation operating system "Windows Vista." The system is scheduled to be released sometime next year (2007). Other operating systems are MacOS (running on Apple computers), DOS, UNIX and Linux. The term platform refers to the underlying hardware and software for a system. For example, the platform might be a Pentium 4 processor running Windows XP. The platform could also be machines running UNIX operating system on an Ethernet network. The platform defines a standard around which a system can be developed. Once the platform has been defined, software developers can produce appropriate software and managers can purchase appropriate hardware and applications. When purchasing additional hardware and software for your system, it is important to know what platform your system is running on. This will ensure that the new hardware and software are compatible with, and will work on the existing hardware and operating system of your computer. Applications software allows you to perform different tasks. Tasks that you work on with a computer are called applications, and the programs or software that you use to perform them are called application programs or applications software. For example, an application could be writing a letter, and the application program you use for this application is a word processing program. Microsoft’s MS Word is one such word processing software. The application program you use depends on the task you want to perform. There are application programs today for practically anything you can think of – in areas of business, personal, desktop publishing, communications, entertainment etc. MULTIMEDIA Nowadays, the typical off-the-shelf PC is configured to run multimedia applications. Multimedia is the combination of two or more media (text/hypertext, graphics, audio, animation and video) into one new, blended, medium. Multimedia applications combine text/hypertext, sound, graphics, motion video, and/or animation. Computer-based encyclopedias, such as Microsoft’s Encarta, online books, movies, music videos and video games, provide a good example of multimedia applications. Long touted as the future revolution in computing, multimedia applications were, until the mid-90s, uncommon due to the expensive hardware required. With increases in performance, and decreases in price, however, multimedia is now commonplace. Because of the storage demands of multimedia applications, the most effective storage media are CDs and DVDs. MNG 210 I. Introduction to Computers 18 But more than just integrating different presentation types, multimedia is expected to allow some form of interactivity, allowing the user a certain amount of control over the flow of the piece. This is multimedia’s true strength. Types of Media Since multimedia is made up of a combination of several types of media to earn its "multi-", it makes sense to examine each of these building blocks individually. Text This includes all alphabetic (uppercase and lowercase) characters, numbers and special characters. Text or Hypertext? Text, by its very nature, is linear. That means that you can usually expect to read any given document from beginning to end. And most of the time the author intended you to do so. Hypertext allows text to follow a flow that doesn't take a straight line. This term was first coined by computer scientist Ted Nelson in 1963, and was conceived as a way to describe non-linear texts. With hypertext, the reader chooses his or her way through a series of interconnected text segments. This may sound more than a little familiar, since the concept of the hypertext was brought to the general public in the form of the Internet and especially the World Wide Web. Documents on the Web are written in Hypertext Markup Language (HTML), and their strength lies in the fact that they can be connected to any number of other documents on the Web. Hypertext is an important part of multimedia, because it puts control of the document flow in the hands of the reader. Even a document containing only text, but linked with hypertext can be considered multimedia, because of the interactivity with the reader. Graphics Text is good, but the old adage still holds true: a picture is worth a thousand words. There are countless types of graphic files, but a few types have stood out over the years as being particularly well suited to multimedia. Types of Graphics .BMP The bitmap graphic is the basic Windows graphic. Because bitmap graphics are uncompressed, they tend to take up a very large amount of disk space. .GIF The Graphics Interchange Format type of graphic uses decent compression, but GIF images can only contain 256 colors. However, because of the small file size and long history of this file type, it is has become a standard, especially on the Internet, for small graphical elements. It is also commonly used for putting animations online (GIF animations) .PNG The Portable Network Graphic (PNG) file type is an alternative to GIF. An advantage to the PNG is that file types can contain more than 256 colors, making it a good choice for complex images as well. It does not support animation, however, which is a MNG 210 I. Introduction to Computers 19 drawback. .JPG JPG (aka JPEG) is the Joint Photographic Experts Group image type. JPGs use a compression method that is best suited to very complex and detailed images like photographs. Because of the small file size for such detailed images, JPG has become the de facto standard for showing photographs on the Internet and in multimedia pieces. The 24-bit format supports 16.7 million colors. Graphical Editing So how do you save and manipulate these different graphic types? You need a piece of software known as an image editor. Windows, for example, comes with a small image editor called Paint for creating and editing simple graphic files. However, for the full digital editing experience, a larger package such as Adobe Photoshop is needed. These larger image editors are very good for detailed photo editing, which includes combining photographs together into new images. There are 2 important factors to consider when using photographs and images on the Web: file size and image quality. If you understand what each format does best and where each formats drawbacks lie, you can make an educated guess about which format to choose for various images when preparing them for display on the web. File size Images will be the largest factor in terms of file size for a Web Site. With many people still accessing the internet using slow dial up modems it's very important to keep file size to a minimum, as people will not appreciate waiting longer than they need to for a huge photo to download. Even for people on faster connections it is still good practice to keep the file size of images as low as possible by optimizing your images. Although the term "Graphic" can refer to all types of images in print and web layout, it generally refers to images that are non-photorealistic. Graphics and Line Art are generally simpler in composition than photos and have large areas of solid color. For graphics images, you will notice that despite virtually no visual difference between GIF and JPG images, the GIF image is considerably smaller than the JPG. GIF images work better for large blocks of color and sharp edges. If you are working on a large Web Site, this difference in file size can quickly add up and increase download times. Image quality JPEG/JPG is ideally suited for compressing photographic images. It has been designed so once the image has been compressed you can not see any difference in quality with the human eye. However if you do zoom in on an image that has been compressed and compare it to the original you will be able to notice a difference, so the more you compress the image to try and save file size the lower the quality of the image will be. When you save your image as a JPG you will be given the option of what quality you want your final image to be; the higher the quality the larger the file size will be. You need to decide at what point you can start to see a visible difference in quality; as a rough guide this is normally around 60%. When the GIF format is used for photographic images, the quality of the GIF image is lower. This is because the GIF image is using its maximum of 256 colors but it still does not have enough colors to MNG 210 I. Introduction to Computers 20 display all the different shades of colors present in the photograph. JPG however can display millions of colors; this is why it is better to use JPG for photographic images. Compare the quality of the 2 photographs below. You can see the lower quality of the image (blurred) on the left which has been saved as a GIF file. In the image on the right, which is a JPEG file, you can see sharp, clearly defined outlines of the mountains, clouds etc. GIF file JPEG file Audio Using the computer to record and create sound/music or playback audio (aka, audio editing) is very much a big part of multimedia. Audio editing Audio can be stored in many different file types, but some of the more common ones you will run across are: Types of Audio files .WAV This is Microsoft's default file type for uncompressed audio. WAV files can contain hi-fi stereo sound, but are extremely large - a 1-minute stereo WAV will take up approximately 10 MB. .MP3 Mpeg Layer 3 is an extremely well compressed audio file. The standard MP3 type, at 128kbps, takes up only 1/10 of the space a WAV file does. The same 10 MB 1- minute stereo WAV file, compressed to an MP3 file, will only take up approx. 1 MB. MP3 is a lossey form of compression, though the loss of audio quality is really only noticeable by audiophiles. 128 kbps MP3 would be comparable to good stereo FM quality. MP3 One media technology that has caused an enormous stir is the MP3 audio compression standard. As described previously, an MP3 file of a music track takes up about 10% of space that the full digital audio MNG 210 I. Introduction to Computers 21 file would, and is almost indistinguishable from the real thing. This gave rise to computer users in the late 90s copying music to files on their computers, and sharing them across the Internet to anyone interested in spending the time to download them. File sharing programs, such as Napster or Morpheus, became commonplace on computers at home and at offices. Naturally, the commercial music industry does not approve of this, since it does involve breaking copyright laws. The industry has claimed since 1999 that MP3 sharing has had a negative effect on music sales. To them it is stealing, not sharing, as most of the people who downloaded these files have not paid for the original albums. MP3 files have become so popular a way to listen to music that a whole industry has grown up around creating portable MP3 devices, and working the technology to play MP3s into existing technologies like CD and DVD players. But MP3 as a technology in itself certainly isn't criminal. MP3 is an incredibly efficient format for musicians to distribute and promote their own music. Plus, music lovers can take their own CDs and, by copying the songs to MP3, put as many as ten or more albums onto one CD-R. So what is the solution? Some argue that MP3 as a format should be outlawed, and technology manufacturers should be discouraged from using it. Others claim that the problem is simply with the people who distribute illegal MP3 songs, and that copyright laws should be more strongly enforced. The debate rages on even today. Audio editing software records incoming audio, edits it and (usually) applies effects to it as well. It can be used for anything from dividing up a recording into snippets of sound, or creating long mixes of songs. Video Video has become another integral part of most multimedia pieces. The advent of digital video has ensured that it's now even easier for people to manipulate recorded video on the computer. Just as the other media types, there are several types of video files that you will most commonly encounter. Types of Video Files .MPEG There are three major types of MPEG (Motion Pictures Expert Group) files: MPEG-1, with a maximum resolution of 352x240 pixels at 30 frames-per-second (fps). Lower quality than television. MPEG-2, with a maximum resolution of 1280x720 pixels at 60 fps. This is the video standard used by DVD videos. MPEG-4 is a newer standard, designed with better compression to bring high quality image and sound over a narrower bandwidth (like the Internet). Quicktime A video file type and standard developed by Apple Computer. Quicktime works very well for streaming video (playing it as it is downloaded - see below for more details on streaming). It is also the basis for the MPEG-4 standard. .AVI This is the file type for the Video for Windows file format, the main video format developed by Microsoft for use in Windows. Digital Video Editing As the price of digital recording equipment becomes more and more affordable, it becomes easier to record live digital video, and transfer it to a computer for editing. This ranges from MNG 210 I. Introduction to Computers 22 people editing their home videos to make them more dynamic, all the way to independent filmmakers shooting and editing quality projects entirely themselves, with a single computer. Even full feature Hollywood films are now being shot completely on digital video. The recent Star Wars movies are a good example of this. Because of this, there are more and more software packages appearing that allow digital cinematographers to do everything themselves, but some like Adobe Premiere or Apple's Final Cut Pro, stand out as popular choices. File streaming Transferring larger audio files, movies, or animations is not always instantaneous over the Internet. Particularly when the host server is located halfway across the world and you're only armed with a 56K modem. To allow people with slower bandwidth to benefit from this type of large file, file -streaming technology saves the day. Streaming works thanks to a process called buffering: the computer downloads a certain amount of the file, then begins playback from the beginning of that buffered data. The idea is that so long as the data is being downloaded and added to the buffer faster than the computer can play it, the user can start playing a file far sooner than it would take to download the whole thing. There are many different types of files and software that are designed for streaming, but some of the most common types you'll encounter are: Real Audio (for streaming audio) Shoutcast (for streaming audio) Quicktime (for streaming video and audio) Real Player (for streaming video and audio) Animation Animation has come a long way since the days of the first animated films, when animators had to draw each animation frame by hand, and photograph them one by one to film. Computer software that allows the user to create animation has existed for a long time, but where computers have truly excelled as animation tools is the process of tweening. Tweening Short for "in-betweening", tweening is where the computer program takes two images, and generates in- between images of the content morphing from the state of the first image to the state of the second. Sometimes you want to add an effect that is graduated over several frames. For example, moving a car from the left side to the right side. Instead of moving the car a little bit on each frame, you can simply: -position the car on the first keyframe, -then insert a keyframe where the car should stop -and finally tell the software for e.g., Flash to tween between the two keyframes. Tweening simply means going from one keyframe to another while taking small steps for each of the ordinary frames in between. The more powerful the computer, the better it is at tweening a greater number of individual objects separately, for more realistic-looking and complex animations. For example, a moving ball would be simple and require tweening only for one object: the ball. To tween a person walking, though, requires many different points tweening at different speeds and in different ways to make the movement look realistic. You MNG 210 I. Introduction to Computers 23 can also morph images so that there is a graduated change from one image to another – for eg. a young man morphing into an old man. Animated GIFs One type of animation commonly found on Internet Web pages is the animated GIF. An animated GIF is a series of GIF images saved into one file, that are displayed one after another to create a simple form of animation. Because animated GIFs are compatible with almost all Web browsers, they are an ideal choice for small animations on the World Wide Web. Animated GIFs can be created in most professional image editing applications (Adobe Photoshop, Macromedia Flash, Macromedia Fireworks), as well as in smaller independent applications devoted specifically to creating and editing animated GIFs. Flash Flash is an animation technology, used primarily for creating and running animation effects in Web browsers. Flash is very Internet-friendly, because: 1. Flash animations can be streamed from the Web server to the browser, making it possible for the viewer to watch the animations as they download. 2. Flash is run from a browser plugin. This ensures that no matter which Web browser the plugin is hosted by, the Flash animation will always look the same. A browser plugin is a small program that is integrated into a Web browser to extend its capabilities. Thus if the webpage is designed to run with something that is not standard to the browser, the viewer needs to down load an additional plug-in. This may be used to run enhanced graphics (Flash), sound (Real Audio) or 3D (Cosmo Player), or other such rich media applications. Macromedia Flash is the main program to create Flash graphics and animations, and probably the most common. Simulation Nothing is more interactive than simulation. Computer multimedia technologies are being used for all sorts of simulations, from virtual tours of museums and galleries, to anatomical simulations for surgeons to practice the latest medicinal techniques. Virtual Tours Many technologies (Quicktime, for example) allow you to create quasi-3D panoramic shots of locations. More than a few real estate and tourism sites on the Internet make use of these virtual tours to give Web site visitors a better idea of the full impact of how a location looks when you're actually standing there. Virtual Reality Virtual reality is using technology that allows a user to interact with a computer-simulated environment so make a person believe that they are immersed in an environment when they actually are not. This is done by tricking the five senses: special screens or glasses make the person see the virtual environment. Headphones allow them to hear the virtual world, and special gloves can even let a person "feel" objects in the virtual reality. For example, medical technology has been pursuing tactile virtual reality as a way to let surgeons practice surgery in a simulation. MNG 210 I. Introduction to Computers 24 Virtual need not be as high-tech as that, though. By extension, any computer world that allows the user to move through it in three-dimensional space can be called virtual reality. Multiplayer games on the Internet that allow players to move their characters through a virtual world and interact with other players in real time are certainly a type of virtual reality. A Massively-Multiplayer Online Role-Playing Game (MMORPG) is a type of online computer role-playing game (RPG) in which a large number of players interact with one another in a virtual world. In an MMORPG, a player uses a client to connect to a server, usually run by the publisher of the game, which hosts the virtual world and memorizes information about the player. As in all RPGs, players assume the role of a fictional character (traditionally in a fantasy setting) and take control over most of that character's actions. The user controls a character represented by an avatar, which he directs to fight monsters for experience, interact with other characters, acquire items, and so on. Impact of Multimedia Home and Business Unsurprisingly, the presence of multimedia in business and home life has changed not only the way activities are carried out, but even imposes a different way of thinking at the conceptual stage. The following pages examine some of these changes more closely. Business Multimedia, during the 1990s, turned into a huge business market in a very short amount of time. Nowadays, at the beginning of the 21st century, multimedia business is divided by the individual technologies, instead of everything being lumped under the one heading of multimedia. More possibilities for marketing, presentation From a marketing standpoint, multimedia opens up huge new possibilities. Instead of just being able to read about a product in a magazine, or watch a television commercial, consumers can visit the manufacturer's Web site to interactively guide their own research into a product. Real estate firms host virtual tours of listings using Quicktime technology. Potential software users can "try out" a program's interface using a Flash-based presentation. The World Wide Web itself basically can be seen as one huge marketing and consumer information database. Kiosks, with computer touch screens and speakers, allow business to carry out more sales transactions automatically. Outside movie theatres you'll find touch-screen ticket vendors where cinema-goers can browse the movies being played, watch trailers, purchase tickets and even concession snacks. Tourism sites will use multimedia kiosks to guide travelers around a site or an area, complete with audio-video presentations and even printers to print out coupons for local businesses. Business opportunities increase each time a new multimedia type emerges. As mentioned above, multimedia is less of a distinct trade these days, and is more like an abstract term that encompasses any interactive technical that involves at least two of the five senses. Both from a manufacturing standpoint and from an authoring side, business opportunities abound every time a new multimedia technology becomes popular. DVD sales have jumped astronomically since the technology's introduction in 1997. Cellular phones where the ring can be customized have created a huge market in sales (and thus the creation of) personalized ring tones based on sound effects, or hit music. MNG 210 I. Introduction to Computers 25 Home With the popularity of DVD and the wide acceptance of the home desktop computer as a necessary household appliance, multimedia is not just a business trend. It's a reality. Watching a movie is an interactive experience, instead of just a passive one. Self-publication The fact that almost all multimedia can be created and prepared for distribution on a home computer is the most amazing thing about it. Anybody with an Internet account can publish multimedia Web sites to the Internet. A CD-burner allows for creation of educational multimedia CD-ROMs, or even just mix CDs of favorite music. DVD-burners take that one step farther and Digital Video camcorders take that one step further. You could record home movies, and with the right DVD authoring application, create DVDs to distribute to family and friends. Many an independent filmmaker these days has started his or her career on the personal computer. Entertainment Nowhere has multimedia changed things in a greater way than in the entertainment industry. Games! Some people seem to eat, breathe, and live video games. But this is certainly increasingly possible, as video games are designed to be more and more an immersive experience. Massively Multiplayer Online Role-playing Games (MMORPGs) like Runescape or Conquer allow players to live and work, almost in real-time, in a virtual world over the Internet. A person who plays a blacksmith in one of these games doesn't just click a button to make a shield. The ore has to be found, mined, collected, and then melted down. The item has to be designed, and then forged. It's almost like real work! Yet people love to do it, day after day. DVD With DVDs, consumers expect more for the money. No longer content to just press play and watch a film from beginning to end, the DVD consumer wants animated menus, voice-over commentary tracks by the film-makers, extra footage, background documentaries, and whatever else DVD authors can add to the package. Watching a movie is no longer a passive role, but an active experience, as the viewer chooses with the remote control what options about the movie to change (some DVDs even offer alternate camera angles), and in what order they experience the added features. Web Never underestimate the power of the Web. This medium in which anyone can self-publish has changed the virtual landscape from one previously devoted only to education and advertising to one where someone can express themselves artistically and interact with others using many different media. Just like people expect more from the movie viewing experience, people expect more from the reading experience on the Internet. Education Self-teaching has always been acknowledged as harder to do than classroom learning. Multimedia, with interactivity being the key component, brings new dimensions to learning. Teachers use the computer in the classroom for multimedia demonstrations and simulations. Using multimedia tools, students can add greater depth to the works they create. MNG 210 I. Introduction to Computers 26 Computer-based Training Multimedia is enormously useful (and has been often used for) self-directed learning. In Computer-based Training (CBT), users run through lessons, exercises, and tests on a computer using pre-prepared multimedia training software. The important key here is that students direct their lessons. On a computer, the students can learn whenever they have time to devote to it, and can move at whatever pace suits their style of learning. The Internet and the Web can take computer-based training even farther, allowing real people to teach others live, no matter where they are located. Real-time animated whiteboards and teleconferencing are two technologies that are being deployed across the Internet to enhance distance learning for students. Virtual reality for training (pilots, doctors, etc.) As mentioned previously, virtual reality is a very powerful tool for practical simulation training that has only just begun to be tapped. Computers can run increasingly realistic flight simulators to help pilots begin their flight training when it's not possible or convenient to use real airplanes. Doctors can be walked through and even participate in, if the technology permits it, virtual surgeries. Hardware Manufacturers Because multimedia has really become part of every day life for many technology users, the consumers want to be able to use their devices to accomplish more. Witness cellular phones with digital cameras, or the large number of multimedia peripherals that are considered "standard" on the home computer (especially soundcard, speakers, and CD-burner). Hardware manufacturers are forced to come up with more flexible devices to keep up to the consumer demands of multimedia. Software Developers Software has to be more all-encompassing, too. Instead of using many small programs to do one or two specialized tasks, users are growing more used to relying on large all-in-one software packages that can be used for a wide variety of tasks and creative purposes. At one time, the Windows platform was just an operating system for keeping programs running on the computer. Now, in Windows XP, the capability to write CDs, copy music, edit digital photographs, and watch DVDs has been built right into the operating system. The typical multimedia-configured PC includes the following components: 1. a microcomputer (including the processor, memory and other electronic components in the System Unit) 2. a keyboard for input 3. a point-and-draw device for input (usually a mouse) 4. a microphone (audio input) 5. a scanner (printed copy input) 6. a monitor for soft copy (temporary) output 7. a printer for hard copy (printed) output 8. a set of speakers (audio output) 9. a permanently installed high-capacity hard drive for permanent storage of data and programs 10. a floppy-disk drive into which an interchangeable diskette, or floppy disk, is inserted 11. a CD-ROM drive into which an interchangeable CD-ROM is inserted MNG 210 I. Introduction to Computers 27 12. a CD-RW drive to record or rewrite CDs 13. a DVD-ROM drive into which an interchangeable DVD-ROM is inserted 14. a DVD-R drive to record or rewrite DVDs 15. USB ports 16. an operating system 17. application programs to perform various tasks for the user References: 1. Classification of Computer Systems. http://www.inetdaemon.com/tutorials/computers/hardware/terminals.html 2. The Birth of the PC. www.doc.ic.ac.uk/~nd/surprise_97/journal/vol1/lpl/ 3. What are the different types of computers? www.howstuffworks.com 4. The IBM PC – History. www.inventors.about.com 5. Information Technology. The Breaking Wave by Dennis P. Curtin, Kim Foley, Kunal Sen and Cathleen Morin 6. IT Bonus Chapters https: http://wps.prenhall.com/bp_capron_computers_8/0,7482,635492-,00.html