IT Essentials ITE 112 MODULE.pdf

IT ESSENTIALS ITE 112 Course Name: Introduction to Computers Course Author: Roger Powley, CD PhD – Commonwealth of Learning Consultant Wilhelmina Louw – Namibian College of Open Learning Glenda Gaye – University of the West Indies Commonwealth of Learning Edition 1.0 Commonwealth of Learning...

IT ESSENTIALS ITE 112 Course Name: Introduction to Computers Course Author: Roger Powley, CD PhD – Commonwealth of Learning Consultant Wilhelmina Louw – Namibian College of Open Learning Glenda Gaye – University of the West Indies Commonwealth of Learning Edition 1.0 Commonwealth of Learning © September 2011 Any part of this document may be reproduced without permission but with attribution to the Commonwealth of Learning using the CC-BY-SA (share alike with attribution). http://creativecommons.org/licenses/by-sa/3.0 Commonwealth of Learning 1055 West Hastings Street, Suite 1200 Vancouver, British Columbia Canada V6E 2E9 Telephone: +1 604 775 8200 Fax: +1 604 775 8210 Web: www.col.org E-mail: [email protected] Introduction to Computers 2 ACKNOWLEDGEMENTS The Commonwealth of Learning wishes to acknowledge the contributions of the course authors and the support of the University of Lesotho in the creation of this course. Introduction to Computers 3 TABLE OF CONTENTS ACKNOWLEDGEMENTS 3 TABLE OF CONTENTS 4 COURSE OVERVIEW 9 Introduction 9 Course Goals 9 Description 9 Required Readings 9 Major Assignment 9 Assessment 10 Course Schedule 10 Hardware and Software 10 STUDENT SUPPORT 11 Academic Support 11 How to Submit Assignments 11 Technical Support 11 UNIT 1: IMPACT AND HISTORY OF COMPUTERS 12 Introduction 12 Unit Objectives 12 Topic 1 – Computer Technology – An Introduction 13 Introduction 13 Objectives 13 Introduction to Computer Technology 13 Computer Technology is Everywhere 16 Generating Information 16 Accessing Information 17 Surveillance 18 Changing the Way We Communicate 18 Topic Summary 19 Topic 1.2 – Information Technology (It) – The Concepts 20 Introduction 20 Objectives 20 What Is Information Technology? 20 Impact Of Information And Communication Technology (ICT) On Society 22 Threats to Information Systems 23 Topic Summary 25 Topic 3 - Computer technology in Work and Play 26 Introduction 26 Objectives 26 Science, Medicine, Health and Technology 26 Introduction to Computers 4  Education and Technology 29 Business and Technology 30 Social Interactions and Relationships 31 Man-Machine Connection 32 Topic Summary 33 Unit 1 Summary 34 UNIT 2: COMPUTER HARDWARE 36 Introduction 36 Unit Objectives 36 Topic 1 – The Evolution Of Computer Technology 37 Introduction 37 Objectives 37 Computer Generations 37 The First Generation Computer (1940s-1950s) 38 Topic Summary 43 Topic 2 – Computer Hardware And Peripherals 44 Introduction 44 Objectives 44 Input Devices 44 Output Device 46 Process and Storage Devices 47 Storage Devices 48 Topic Summary 53 Topic 3 - Computers and Computing 55 Introduction 55 Objectives 55 General Purpose Computer Systems 55 Embedded Computer Systems 56 Computer System – How It Works 57 Topic Summary 61 Topic 4 – Processing Data 62 Introduction 62 Processing Data and Computer Memory 62 Topic Summary 65 Recommended Unit Readings 66 Unit 2 Summary 67 UNIT 3: SOFTWARE 69 Introduction 69 Topic 1 - Operating Systems, Utility Programs and Language Translators 71 Introduction 71 Introduction to Computers 5  Operating Systems 71 Types of Operating Systems 73 Functions OF AN Operating System 74 User Interface 76 Utility Programs 78 Language Translators 79 Topic Summary 80 Topic 2 – Applications Software 81 Introduction 81 Objectives 81 Personal Productivity Applications 81 Word Processing Features 83 Workgroup Applications 83 Enterprise Applications 83 Application Software Development 84 Spreadsheet Features 84 Presentation Software Features 85 Proprietary versus Open source software 85 Topic Summary 86 Recommended Unit Readings 87 Unit 3 – Summary 88 UNIT 4: FILE AND DATA MANAGEMENT 91 Introduction 91 Unit Objectives 91 Topic 1 - Disk and File Management Operations 92 Introduction 92 Objectives 92 File Management 92 Root Folders and Subfolders 92 Creating and Deleting Folders 95 Disk and File Management Operations 96 Topic Summary 97 Recommended Unit Readings 98 Unit 4 - Summary 99 UNIT 5: INPUT AND OUTPUT DEVICES 100 Introduction 100 Unit Objectives 100 Topic 1 - Keyboard and Pointing Input Devices 101 Introduction 101 Objectives 101 Data Input 101 Introduction to Computers 6  The Keyboard 102 Pointing Devices 103 Topic Summary 106 Topic 2 - Data Entry at the Source 107 Introduction 107 Objectives 107 Source Data Entry 107 Biometrics 107 Scanners 108 Barcode Reader 109 Magnetic Ink Character Recognition (MICR) 110 Magnetic Strip Reader 110 Optical Mark Reader 110 Audio Input 112 Digital Input 112 Topic Summary 113 Topic 3 - Softcopy Output Devices 114 Introduction 114 Objectives 114 Softcopy Output Types 114 Topic Summary 116 Topic 4 - Hardcopy Output Devices 117 Introduction 117 Objectives 117 Hardcopy Output – An Overview 117 Other Types of Printers 119 Terminals – As Input and Output Devices 119 Topic Summary 120 Topic 5 - Storage Devices 121 Introduction 121 Objectives 121 Overview 121 Categories of Storage Devices 122 The Storage Hierarchy 125 Topic Summary 125 Recommended Unit Readings 126 Unit 5 – Summary 127 UNIT 6: COMMUNICATIONS AND CONNECTIVITY 129 Introduction 129 Unit Objectives 129 Topic 1 - Communicating Using Technology 130 Introduction 130 Introduction to Computers 7  Objectives 130 Communications 130 Transaction Processing 131 Information Retrieval 131 Electronic Mail and Electronic Messaging 132 Efficient and Effective Communication 132 Topic Summary 133 Topic 2 - Connecting Computers 134 Introduction 134 Unit Objectives 134 Communication System Components 134 Network Topologies 135 Local Area Networks (LANs) 136 Peer-to-Peer Networks 137 Client-Server Networks 137 Wide Area Network (WAN) 137 Connecting to the Internet 138 Dial-up Internet Connection 138 Other Internet Connections 138 Search Engines 140 Topic Summary 142 Recommended Unit Readings 143 Unit 6 – Summary 144 COURSE SUMMARY 146 Final Assignment Description 148 Course Summary 148 APPENDIX ONE – SUGGESTED RESPONSES 149 Unit 1 Activities And Responses 149 Unit 2 Activities And Responses 154 Unit 3 Activities And Responses 158 Unit 4 Activities And Responses 160 Unit 5 Activities And Responses 161 Unit 6 Activities And Responses 165 Introduction to Computers 8 COURSE OVERVIEW Course Title: Certificate 03 - Introduction to Computers. INTRODUCTION The Introduction to Computers course will prepare future entrepreneurs to operate computer hardware and software applications. Participants will gain an understanding of computer hardware, operating systems, office applications and networks. It will ensure the entrepreneur is able to apply the concepts of networks, the Internet, World Wide Web, and mobile technologies and how they could potentially support a successful business operation. COURSE GOALS Upon completion of the Introduction to Computers course you will be able to: 1. Examine the impact of computer technology on society, education, industry, government and business. 2. Operate a personal computer and computer peripherals. 3. Explain effective computer practices such as backup, updating, troubleshooting, etc. 4. Explain the differences between network software, operating software and application software. 5. Produce simple documents and presentations using Microsoft Word and PowerPoint. 6. Describe a typical network and network hardware. 7. Explain the difference between the Internet and World Wide Web. 8. Explore and search the World Wide Web using a browser to research information. DESCRIPTION This course is the first of two course discussing information technology and its use in the creation and growth of a business. The second course “Business Information Systems” builds upon this course and provides the details of how to use information systems to ensure business success. REQUIRED READINGS Recommended readings are provided at the end of each unit. Most readings will require access to the Internet to review the online articles and web sites. MAJOR ASSIGNMENT The major assignment for this course is to produce a detailed analysis of the hardware, software and network requirements for a small business and its growth over three to five years. The assignment will require the participants to produce the following: 1. Three to five page report using a word processor of your choice (e.g. MS Word, Open Office Word, etc.). Introduction to Computers 9  2. Presentation of five to ten slides that describes the technology solutions reflected in the written report. The slides must incorporate graphics. The participant may select the presentation software to be used to produce the project presentation. 3. The third part of the assignment is to create a spreadsheet that illustrates to cost of the equipment and the annual operation of the technology support required by the business. You should include the creation of a web site as part of the marketing solution. Participants may select the spreadsheet software to be used to produce the budget. 4. All three files should be emailed to your instructor for feedback and review. More details are provided in the Course Summary. ASSESSMENT Assessment and grading will be established based on the instructor’s additional requirements and the institutional policies guiding course assessment. COURSE SCHEDULE The instructor will provide a proposed course schedule based on the length of the semester and any additional assignments or activities that he or she requires of the course participants. HARDWARE AND SOFTWARE Computer Requirements: This course requires that you have access to a printer and computer with Office software that is connected to the Internet. Your institution may provide access to their computer lab or you may use your home or local community computer resources. Software Requirements: Each student will be required to have access to Microsoft Office or Open Office that includes a word professor, presentation software, spreadsheets and data base program. Open Office is an open source equivalent of Microsoft Office and can be downloaded free from the Internet. Introduction to Computers 10 STUDENT SUPPORT Note: This section should be customized based on the services provided by each institution’s capabilities. ACADEMIC SUPPORT How to contract a tutor/facilitator (Phone number, email, office hours, etc.). Background information about the tutor/facilitator if he/she does not change regularly. Alternatively provide a separate letter with the package describing your tutor/facilitator’s background. Description of any resources that they may need to procure to complete the course (e.g. lab kits, etc.). How to access the library (either in person, by email or online). HOW TO SUBMIT ASSIGNMENTS TECHNICAL SUPPORT. Introduction to Computers 11 UNIT 1: IMPACT AND HISTORY OF COMPUTERS INTRODUCTION Technology influences different areas of society and business, whether it is a particular age group or gender, or the entire population. We may be resistant to its influences, whether in the long or short term, until we are more aware on how this change impacts our lives, families, work, entertainment, or daily living. This unit explains terms associated with computer technology, explains its influence, and contributions to various aspects of work and play. Then it briefly reviews the development of the technology and explains the different categories of computer systems. UNIT OBJECTIVES At the end of this unit, you should be able to: 1. Define terms and explain characteristics associated with computer technology. 2. Discuss the influence of computer technology in a society. 3. Discuss the contributions of computer technology to education. 4. Discuss the contributions of computer technology to business. 5. Discuss the contributions of computer technology to everyday living. This unit is divided into three topics: Topic 1: Computer Technology – An Introduction Topic 2: Information Technology – The Concepts Topic 3: Computer Technology in Work and Play Introduction to Computers 12 TOPIC 1 – COMPUTER TECHNOLOGY – AN INTRODUCTION INTRODUCTION Computer Technology is now part of our everyday life, and almost every task we encounter involves the use of computer technology. This Topic will first help you to understand computer technology and its impact in society. OBJECTIVES After studying this topic, you will be able to: 1. Explain terms associated with computer technology. 2. Explain features of computer technology. 3. Explain features of computer technology. 4. Discuss the extent to which computer technology has increased access and flexibility. 5. Discuss the extent to which computer technology has changed the communication landscape. INTRODUCTION TO COMPUTER TECHNOLOGY Let us start by understanding the concept of computer technology. Quickly, in 30 seconds, calculate the answer to 12 + 54 + 23.65 + 12.89 + 23¼ + 90 + 12 + 980 + 234 + 567 in your head or on paper. Did you complete it in time? See the next page for the answer. You may be surprised to learn that people were the first computers! The term computer means someone who computes or performs calculations. Centuries ago, people were called computers. They were usually women who worked out mathematical problems such as tidal charts or navigational tables, and so ‘Computer’ was actually a job title. However, as you can imagine, performing mathematical tasks every day, every week, every month would eventually cause boredom which would cause errors in the calculations. Therefore, the computer became a machine which automated these repetitive tasks. A computer therefore is a machine which: accepts data (called INPUT); follows instructions given on what to do with the data (called PROCESSING); stores the results for future use (called STORAGE); and Introduction to Computers 13  display the results (called OUTPUT). Answer: 2008.79 By applying technology to different problems and work environments we can enhance situations or events that would have been almost inconceivable without it. For example, voice mail, satellite television or cell phones are all examples of technology that use a computer to operate the system. Computer technology therefore involves any machine, tool or piece of equipment that is essentially controlled by a computer chip that is able to make calculations. The role of computers and computer technology is the ability to manipulate data into information or commands. Data can be in many forms, such as text, pictures or sound and can also be retrieved from the environment. An air conditioner which monitors the temperature in a room to keep it cool at a specific temperature, or turning on lights outside a building at dusk are both examples of a computer controlled environment that requires input to produce a specific result or output. Air Conditioner Automated Lights Input Current Temperature Dusk Desired Temperature Output AC adjusts temperature to Lights On desired temperature Activity 1.1 - Consider why it is essential that data and information must have the following qualities: Relevant Complete Accurate Clear Reliable Concise Timely Turn to Appendix One for Suggested Response Introduction to Computers 14 Introduction to Computers 15 COMPUTER TECHNOLOGY IS EVERYWHERE Information has become very important as a result of the computer technology which provides it. Computer driven technology is an integral part of our daily routines, however we tend not be aware of its presence. Many of our daily tasks are automated; such as our answering machines, televisions, cable boxes, vehicles that use this technology. Similarly, as a cashier prints out our receipt for a purchased item or the mail we receive that was stamped by a machine, computer technology supported the creation of the receipt or the delivery of our mail automatically. We therefore say that computer technology is ubiquitous, or everywhere (almost!) once information is present. To summarize, many utility companies are now recording our usage to prepare monthly bills, which will be printed by a machine, while a local or overseas phone companies record voice messages and the calls we missed. Also, our banks’ automated systems are automatically charging us every time we use the debit or credit card. The automated systems are controlled by a computer process based on the input from your retailer, the machine itself or from the scanner. Activity 1.2 - Describe how computer technology is integrated in the following sectors: Agriculture Education Theatre or the Arts Turn to Appendix One for Suggested Response GENERATING INFORMATION Remember that computers store the results or output of processing the data. Well computer technology has enabled us to access information at our "finger tips"; from many places, in many places, at any time, and in many different forms whether printed or stored. Hence as more information is requested, more information is generated and more data stored. It seems like a never ending cycle of information growing exponentially! Activity 1.3 – Think of some specific examples, that you could use to explain what is meant by the phrase: “… computer technology has enabled us to access information … from many places, in many places, at any time…’ Turn to Appendix One for Suggested Response Introduction to Computers 16 Unfortunately, there is a drawback to generating information on every transaction. Imagine how one minor error can mushroom into major problems because of your computer technology, and this can have a negative impact on businesses and customers alike. In addition, most people who are not in the computer field may believe that whatever the computer produces is correct. Consider the consequences of transposing (switching) two digits in a bank account number or entering the wrong data in payroll system. This can cause embarrassment to the persons involved if deposits are made to the wrong account or employees do not receive the correct pay. Even so, it is also more difficult to locate someone who is willing to accept responsibility for an error made by a computerized system. This lack of accountability for the error would be better addressed if the software glitch was corrected as soon as possible! We should also realize that since information is constantly generated, then it should be possible to store it over a long period of time. It is reasonable to assume therefore that information cannot be entirely destroyed or lost. Activity 1.4 - Describe two procedures or methods that should be implemented to ensure that information is not lost or destroyed. Turn to Appendix One for Suggested Response ACCESSING INFORMATION Much of the computer information that is generated and held in a database is available on- line. For example, customers can use the telephone or Internet to access current bank balances and perform transactions. Access to your banking information can be made from almost anywhere in the world. This has led to a new work ethic where computer technology has enabled employees to work from various geographic locations, or time zones. Computer technology has provided people with increased mobility while talking with someone on the phone, or receiving a fax. Information can be retrieved and sent in many forms including text, voice, graphics, photos and video. Additionally, the "information superhighway" has increased the availability of these forms of information delivery methods. One major concern of the recording industry is the ability to reproduce digital material such as video tapes and DVDs, which are indistinguishable from the original. This technology has caused headaches to the industry’s composers and performers since any digital file can be easily duplicated and shared. Activity 1.5 - How would you explain the term "information superhighway" to a family member? When considering your explanation highlight some characteristics that are implied in the term. Turn to Appendix One for Suggested Response Introduction to Computers 17 With access to information, and digital voice and smart technologies automated voices have replaced operators who traditionally greeted customers and initially responded to their queries. It is now commonplace to call businesses and hear an automated switching system and voice-mail system instead of an actual person who can assist you. Activity 1.6 - Think of three companies in your country that have automated responses to transfer you to an extension or department. Consider how hearing an automated response or a human voice personally affects you, and what these effects are. Turn to Appendix One for Suggested Response SURVEILLANCE Computer technology has certainly allowed surveillance or the gathering of information for different of purposes. Surveillance software allows individuals, companies and government to monitor you in a variety of locations including other countries. Surveillance equipment such as cameras and key pads now include transactional data which is collected from virtually all types of transactions, including cash purchases and the acquisition of services to analyze trends. One example is the use of Google Earth to capture topographical pictures of different locations on the earth and more recently Google has released their street view software that allows you to wander the streets of your city using 3D technologies. Take a look at it by clicking here. Activity 1.7 - After viewing Google Street View, consider why investigators would want to use surveillance to analyze pedestrian traffic in a town, or weather patterns in a particular area of the country. Turn to Appendix One for Suggested Response CHANGING THE WAY WE COMMUNICATE With the use of the computer and its technology used extensively throughout our society, you are probably aware of how computer technology has changed the way we communicate with another person or among groups of people. The use of email, instant messenger and text messages have modified the usual visual and verbal signs when communicating with someone else. This of course can be both a benefit and a detriment to the communication process. For example, the use of computer tools such as email, instant messenger and text messages mask features such as gender, race, age, and physical disability, social or marital status. Even distance learning has changed the way people are educated, as this manual and your online activities illustrate! Your relationship with the facilitator is remote and you may only Introduction to Computers 18 hear a voice or read the words on a page written by your instructor. Much of the distance or blended learning materials and content are delivered though the use of databases, audio or video feeds and other means such as Moodle or Blackboard. This has become a reality for many who wish to further their education while employed full-time or those who are unable to access a physical campus at a local institution.. Activity 1.8 - Identify: Different symbols that are used to represent emotions in email messages, instant messenger and text messages. Think of different words or phrases that have been shortened or modified in email messages, instant messenger and text messages Turn to Appendix One for Suggested Response TOPIC SUMMARY During the review of this topic we learned that computers impact every aspect of our life. As a future entrepreneur you must learn to recognize the potential of computer technologies and how to incorporate them into your business environment and business plan. Consider the type of information you need access to, the type of information your customers need and how to communicate this information to your target audience. The next topic discussion on “Information Technologies” will help you better understand the concepts related to computer and information technologies and provide another perspective on how IT impacts our lives. Introduction to Computers 19 TOPIC 1.2 – INFORMATION TECHNOLOGY (IT) – THE CONCEPTS INTRODUCTION As noted in Topic 1.1 computers play a major role in our daily lives. Business demands the use of computers to support business operations. As an entrepreneur it is important that you understand and use computer technologies effectively to help grow your business. Before exploring the details of a business computer environment, you need to understand what we mean by information technology and how it influences society. OBJECTIVES Upon completion of this lesson you will be able to: 1. Define information technology. 2. Explore the main uses of computers in society. 3. Describe the impact of computers on society, education, industry, government and business. WHAT IS INFORMATION TECHNOLOGY? Let’s first look at some key terms before we define the concept information technology. Let’s start with the term information. Information refers to data that has been put into a meaningful and useful context. Information systems refer to a set of people, procedures and resources that collects, transforms, and disseminates information in an organization. Information systems are implemented within an organization for the purpose of improving the effectiveness and efficiency of that organization. As an entrepreneur you will need to use a system to provide for the flow of information within your business. Computers is playing a vital part in obtaining, processing and sharing information within a business which means that an entrepreneur will have to make use of a computer-based information system. This requires that you must have an understanding technologies used in computer-based information systems – use of hardware, software and people resources to transform data resources into information. Back to our question: What is meant by Information Technology? Information Technology (IT) is the area of managing technology and spans a wide variety of areas that include but are not limited to things such as processes, computer software, information systems, computer hardware, programming languages, and data constructs. In short, anything that renders data, information or perceived knowledge in any visual format Introduction to Computers 20 whatsoever, via any multimedia distribution mechanism, is considered part of the domain space known as Information Technology (IT) (Wikipedia). TechAmerica defines IT as the study, design and implementation of computer based information systems, particularly software applications and computer hardware. IT deals with the use of electronic computers and computer software to convert, store, protect, process, transmit and securely retrieve information (www.answer.com). The discipline of Information Systems can best be described as the effective analysis, design, construction, delivery, management and use of information and information technology in organizations and society. An Information System, per se, is an organized collection of people, procedures, data, machines and services that work together to deliver information (http://www.is.ru.ac.za/?q=content-2 ). So we can conclude that: Information technology (IT) refers to the different ways (electronic computers and computer software) of obtaining, processing, storing, and transmitting data in the form of voice, pictures and words. The term Information Technology (IT) is also known as Information Communication Technology (ICT), and we shall continue to use that term henceforth because it combines computing and communications. The computer is a key feature of ICT and the key to an effective business is how the entrepreneur uses his or her ICT resources to grow and manage the business. It is clear from our brief discussion that computer technology plays a vital role in everyday life. Now take a few minutes to complete the following activity. Introduction to Computers 21 Activity 1.9 - You have no doubt have come across a computer of some kind in your everyday tasks, be it directly or indirectly. Do you agree? In Column A, list five places where computers can be used in operating a business or in your local community and in Column B suggest how the entrepreneur can use these computers to support ICT. Turn to Appendix One for Suggested Response PLACE USE You might have referred to places such as schools, businesses, government institutions and the individual at home. Work through the following information and compare it with your answers for this activity. IMPACT OF INFORMATION AND COMMUNICATION TECHNOLOGY (ICT) ON SOCIETY Today’s society is referred to as the ‘digital age’. Computers and ICT devices have become an integral part of our lives and are used everywhere. Be it the desktop computers, laptop computers or more recently tablet computers, all contribute to the activities we experience in our daily life. We use these devices in schools, at home, hospitals, institutions, businesses and even in government offices. In general the impact of computers on society and how we live our lives is as follows: You can use computers to communicate with your family and friends, create a household budget, book travel and movie tickets, or manage your business. The internet has also tremendously increased people’s ability to communicate with others from all over the world efficiently and relatively cheaply. Introduction to Computers 22  In business and industry, you use computers to maintain accounts, create personnel records, track inventory, prepare presentations and reports, manage projects, and communicate by e-mail. You can use computers to design any type of publication ranging from simple newsletters to fashion magazines, marketing materials, books, or newspapers. In the field of education, trainers can use computers to deliver training through audio-visual learning aids, maintain student records to track performance, search for information on different topics, and create or submit assignments. In government organizations, you use computers to organize information by storing and updating records. Computers are also used for providing services to citizens. For example, you can view information on current policies and government issues on a computer. In the field of medicine, doctors use computers to review medical records of patients. Doctors also use computers to find information about the latest drugs available to treat a disease. Doctors can also use computer technology to discuss and share information about various diseases. You can use computers to view the details of your bank account. Traders use computer technology to get instant information on stock markets, to trade stocks, and to manage investments. Scientists use computers for scientific research, and to gather and analyze information. For example, they use computers to view images from space and to publish information on their recent research. You can also use computers to create drawings and paintings. Photographers use computers to edit and enhance pictures. Writers use computers to write content for their books and to also create illustrations. By using computers, writers can make changes in the content easily and save a lot of time. In the field of entertainment, you can use computers to listen to music, watch movies, store and print photographs, send greetings, and play games. [Source: Microsoft Corporation] THREATS TO INFORMATION SYSTEMS Computer-based information systems are much more vulnerable to crime and abuse, natural disaster, and even human error than manual systems that they have replaced. A Computer Crime Introduction to Computers 23  Computer Crime ranges from the use of information technology to commit an act that would be criminal no matter how committed (such as the theft of money or other property) to activities more specifically related to computers, such as the unauthorized access and use of information systems, theft of computer and telecommunications services, and the theft, intentional alteration, or destruction of data or programs. The protection of customer data and business confidential information is an issue that faces all entrepreneurs. B Theft of Money As financial institutions become more and more reliant on computers, new opportunities have arisen for criminals to use computers to steal or siphon off money. Password protection and other security tools must be used to protect bank accounts, investments and other financial resources. C Theft of Computers and Computer Parts As computers and the various computer parts have become smaller and smaller, it have become easier to steal. Microprocessor chips, memory chips, motherboards, modems, disk drives, and power supplies are all frequent targets. They can be removed relatively easily and sold to a readily available underground market. Physical security and effective inventory control measures should be implemented. D Alteration or Destruction of Data and Programs Another form of computer crime involves the alteration or destruction of data and programs. Motives for this crime may include monetary gain, revenge or just being malicious. This tie in with computer viruses, which are a set of illicit instructions implanted within a program that passes itself onto other programs with which it comes into contact. Appropriate software must be used to protect your business files, data and other online resources from external and internal attacks by cyber criminals and hackers. E System Disasters In addition to computer crime, information systems are susceptible to natural disasters (Rain, earthquakes, fire and floods), terrorist attack, electrical power and telecommunications line failure, hardware and software malfunction, even human error. Off-site backups and in some cases backups to computers in another island or nation is recommended when your region is subjected to regular national disasters. Introduction to Computers 24 Now do the following activity to test your understanding of the positive and negative impact of computers and ICT on society. Activity 1.10 - Read the following case and reflect on the information before you look at the questions that follow. In 1999, heavy rains collapsed the roof of a computer centre in Pretoria, knocking out computers that handled transactions for over 4000 ATMs nationwide. As a result, over 1 million cardholders were temporarily deprived of their access to their funds through other teller networks, but because those networks lacked data about account balances, cash withdrawals were limited to R100 a day to reduce fraud. Hint: Think of examples of how technology impact (both positively and negatively) your life personally and how it will impact the entrepreneur in his business. Turn to Appendix One for Suggested Response It is advised that you share your ideas/answers with fellow students by engaging in face-to face discussion, via e-mail or use social media such as Facebook and Skype. This brings us to the end of topic 1. Hope you did well in doing the activities. Let’s summarise what we have discussed. TOPIC SUMMARY In this topic we have learned that: Information technology refers to the different ways (electronic computers and computer software) of obtaining, processing, storing, and transmitting data in the form of voice, pictures and words. Computer technologies directly and indirectly impact society, business and industry, education and government. Individuals and different organisations use computer technology for communication, to provide services to citizens, to record transactions, do banking, listen to music, and do drawings and paintings, to do research and many more functions. IT also poses threats to society. Threats include computer crime, theft, system disasters and alteration/destruction of data and programs. Now as we are through with defining information technology let’s move on to the next topic where we will discuss the basics of computer in detail. Introduction to Computers 25 TOPIC 3 - COMPUTER TECHNOLOGY IN WORK AND PLAY INTRODUCTION Now that we have understood some terminology and features of computer technology, let us look more closely at various aspects of work and play, and how technology affects each one. This section will allow discussion on some of the impacts in the last, and thoughts on the next decade. Inventions already introduced into society through computer technology, have caused the society to change, with the cellular phone (or cell phone) being the most recent to reach the populations. It is now an everyday occurrence to reach anyone, anywhere with the use of a cellular phone. Not as openly known, but still commonplace however, is the use of the smart prosthesis on someone who previously could not walk after an accident. Simulations of people walking or running for example have furthered the invention of essential types of prostheses. OBJECTIVES After studying this topic, you will be able to: 1. Identify the advantages and disadvantages of computer technology in various aspects of society. 2. Discuss the man-machine connection. SCIENCE, MEDICINE, HEALTH AND TECHNOLOGY Simulation and simulators are often used in scientific research to mimic the event that is being studied. These programs quickly perform number crunching calculations, so that the event can be accelerated, slowed or changed to help predict and test certain outcomes. Therefore programs can assist with the simulation of training in dangerous situations, without using expensive resources. Activity 1.11 - Consider the benefits of simulations in each of the following: Space travel Weather Disaster prevention and recovery Loss of limbs Turn to Appendix One for Suggested Response Introduction to Computers 26 Since health care matters to everyone, it is not surprising that computer technology has become a natural part of our health and wellbeing, but its use and relevance has implications in everything we do…and not do! If you would like to explore how medical organizations are using simulation and other computer technologies to provide professional development to health care professionals and support science education in the schools go to the Howard Hughes Medical Institute, Bio-interactive site. Computer technology is integral part of the health and wellness sector. CTI scanners and other diagnostic tools are driven by computer technology. Our health records are placed into databases to be used and retrieved when you visit the hospital or your local doctor. Science has had an incredible impact within the last century. Toffler in his book “The Third Wave” has identified computer technology as a new phase in the evolution of society. Technology has made the following medical procedures possible. Many of these procedures have generated considerable debate about the ethics of these procedures. Some of these procedures include the use of technology to support: test tube babies; organ transplants; cloning; nuclear radiation; limb replacement; gene therapy; and nerve regeneration. Telemedicine Some of you may have previously seen or heard the terms teleconferencing or telecommuting. The Greek word 'tele' means ‘distance’, so teleconferencing provides opportunities to have a conference without all persons having to be in the same room, city or country. Similarly telecommuting or the less popular term, ‘tele-working’, was first offered in the 1960s by the information technology industry. This arrangement allowed employees to work at home and communicate with the office by methods such as phone, fax and computer. So we now have yet another term ‘telemedicine’, where ‘medicine’. Telemedicine involves telecommunications, where medical personnel and their patients are separated by some physical distance but are connected through technology so the professional can complete a medical procedure. Some of the services offered by telemedicine include medical Introduction to Computers 27 diagnoses, pathology, radiology, and consultation, so that expertise can be made available in rural and remote areas. Medical Self-Diagnoses Many people are using knowledge-based database systems to research cures and symptoms of ailments, probably for self-diagnoses. These database systems, called expert systems perform tasks that would otherwise be performed by someone with expertise in the field. Expert systems can be used, not only to diagnose human illnesses, but also to make financial forecasts, and schedule routes for delivery vehicles. However it is important to note that while some expert systems replace human experts, there are others designed to assist them. Having a medical complaint which is embarrassing should not be the sole reason to avoid consulting a doctor. Although there are well-documented and researched medical expert systems (such as WebMD) being able to access a website on the Internet to diagnose symptoms does not automatically validate the authenticity or correctness of the online diagnosis. Only a doctor can do this. Activity 1.12 - Why would you and others want to perform self-diagnosis using an Internet medical search engine? Think about the precautions that you must consider when using such search engines. Turn to Appendix One for Suggested Response Database technologies are now used to store dental records, x-rays, medical insurance forms and other records for administrative, management and cross referencing. Here are some further examples of the development of database systems with associated technologies which are used as expert systems and have become tools for medical research. Research Research on genetics has discovered entire sets of genetic instructions in the cells of our body, their sequences and any possible unique features or abnormalities. Using computer technology has afforded: The discovery of a gene which has the pre-disposition to develop colon cancer can save a life if genetic screening is done early. In contrast, persons in the early 1970s were either denied insurance coverage or were asked to pay increased premiums if they carried the gene for sickle cell anemia. Introduction to Computers 28 Forensic personnel used computer technology to assist in the identification of people missing at the World Trade Centre. Tools were used to compare the victims’ DNA with an item used by the victims, such as a toothbrush. Activity 1.13 - Consider the moral and ethical implications for using computer technology to search databases for screening employees DNA; for other diseases such as HIV/AIDS; or for conducting criminal background checks. Turn to Appendix One for Suggested Response EDUCATION AND TECHNOLOGY Computer technology has moved the classroom from a teacher using a ‘chalk and blackboard’ to deliver passive instruction to student centred, discovery learning environments that employ a variety of computer and Internet technologies. Computer technology has allowed disenfranchised students in places like rural areas who at one time could not participate in traditional instruction to benefit from an anywhere, anyplace philosophy for the delivery of educational programs. In Barbados, technology is now becoming a part of the classroom with the assistance of a government sponsored educational initiative called Edutech 2000. This programme is providing training in Information and Computer Technologies (ICTs) for teachers and students alike in order to develop the country’s future workforce and ensure the country has suitable skills to compete in the international market. In most countries today the typical public school program includes some instruction in computer technology, computer literacy skills and software familiarization. Most public schools throughout the Caribbean and parts of Africa have access to computers within their schools. Technology is being used to support instruction and increase student and teacher technical knowledge and skills. The introduction of computers to support classroom instruction has met mixed reactions. Some teachers embrace it, but many resist it because they don’t have the pre-requisite skills to properly employ the technologies. Change will take time, resources and more teacher professional development. The Commonwealth of Learning is supporting the Open School Movement and the use of ICT to support instruction and student learning. Check it out. Computer technologies and the advent of the Internet have allowed online universities to flourish. Examples of fully online universities include Indira Gandhi National Open University, National Open University of Nigeria, Athabasca University and the Open University of the United Kingdom Online universities and similar organizations around the world provide opportunities for millions of students to study anywhere and at any time. Introduction to Computers 29 Working professionals are now able to further their education without having to travel while maintaining full-time employment and an appropriate quality of life. There are some disadvantages however with online activities, which include the lack of opportunity for human interaction and socialization. Many online students experience the feeling of isolation. Although the inclusion of online discussion forums and chat capabilities have somewhat alleviated this problem, there is still an issue with misinterpretation and miscommunication associated with text messages and phrases. The online learning environment is slowly embracing new technologies like Podcasts, social networking software like Facebook, instant messaging technologies like Skype and web conferencing systems like Elluminate. Web 2.0 tools are helping close the social divide and providing more opportunities to interact with peers learners and others in the educational communities. Activity 1.14 – Based on your own experiences with distance education, think about the potential impact that an online university has on its students. Turn to Appendix One for Suggested Response BUSINESS AND TECHNOLOGY Computer technology has had a major impact on day to day business operations. Today companies that have failed to incorporate technology are viewed as being ‘not-up-to-date’ or archaic. Today organizations must have a presence on the Internet. Their company’s goods and services must be marketed online. Prolific use of electronic mail (or email) and electronic forms have replaced paper based forms and traditional snail mail (letters mailed through a post office). It is now the norm for business professionals to use technology to produce every memo, envelope, label and document using a word processer. Effective marketing materials require the use of graphic software and more to create and produce the layouts. Business presentations are created using computer software and delivered via laptop computers and projectors. Electronic payments and business banking accounts require the use of e-commerce software and secure Internet connections. The computer revolution has allowed traditional businesses to reduce infrastructure costs by allowing their employees to work from home. In North America over 40 million employees work from home using different types of Information and Communications Technologies (ICTs). As traditional business practices become automated business leaders and HR personnel now demand that their current and future employees be computer literate. In the many parts of the developing world it is proving to be a challenge for those who are unable to reach the required standard thus impacting their employability. Introduction to Computers 30  Activity 1.13 – Consider the following and if you have opportunity discuss it with others. What statement best reflects your belief about computer technology and the automation of tasks in the workplace. 1. ICT increases productivity in the workplace. 2. ICT hinders productivity in the workplace. 3. ICT has had no impact on workplace productivity. SOCIAL INTERACTIONS AND RELATIONSHIPS The ability to text chat in a real time environment with your peers is known as Internet Relay Chat (IRC). IRC tools to support chat are available through your cell phone provider or on the Internet. Some of the more popular real time chat tools include Microsoft Live Messenger, Yahoo Messenger and others. These tools are becoming the norm for social interaction (especially among younger computer users) and it challenges in how people have traditionally interacted with each other – face to face discussions vice text chats with its own sub-culture language. As the cartoon below illustrates texting has become part of our culture. I suspect there were smiles as you read the cartoon, but has the cartoon become a reality today? Are people unknowingly hiding behind the technology in order to minimize communicating with each other? Do people speak more freely with the use of technology or in person? Over the years the Internet has evolved from a deliverer of static information text based technology to a platform that encourages social networking, idea exchange, collaborattion and online community building. Tools like Facebook, Yahoo Groups and others allow Introduction to Computers 31 individuals to connect with individuals of like minds and create their own virtual network of friends and colleagues. Tools like YouTube and Blogger have allowed everyone to create and share their own information. Everyone has opportunity to contribute to the world knowledge base and provide their own interpretation of personal, local, regional or national events. This form of the Internet is known as Web 2.0 and has democratized our virtual space. Everyone is now equal and can post personal messages for the world to read. Activity 1.16 – Search the Internet and see if you can discover other social networking sites that you would like to participate in or share with your peers. If you have a course web site or email list feel free to share you link with others and describe why you think your site reflects the values of community building, social collaboration and knowledge sharing. MAN-MACHINE CONNECTION I would hope by now that you would agree much of the world cannot live without having some form of computer technology in their lives. Does this mean that we are controlling computer technology or is the technology controlling us? During the late 1980s and 1990s, the Internet invaded our lives. Movies and TV shows included the Internet and sophisticated computers to entertain us. Some interesting ones were the 1982-1986 weekly television crime fighter series ‘Knight Rider’ which portrayed a modern-day hero who drove a high-tech smart car equipped with artificial intelligence. Sandra Bullock’s 1995 movie ‘The Net’, involved an Alfred Hitchcock style drama about having her identity electronically erased and replaced with a stranger’s information. Then in 1998, there is Will Smith starring in ‘Enemy of the State’ which speaks about the use of satellites to track people, as well as in ‘I Robot’ in 2004 about a ‘humanoid’ robot that is suspected to have murdered its creator. Whether you have seen these movies or not, the implicit use of computer technology in each of them sends the message that whether to help or hinder, that technology is everywhere. Today it is digitally generated 3D movies and animations like Avatar have caught our attention. These movies would not be possible without computer generated images and human machine interactions to capture life like character movement. Technology has advanced so fast that more and more computers have an incredibly high fault tolerance, with robots automating the repair process, without any human intervention. One example are the robots that are used by NASA to repair the International Space Station. Seriously, we are not that far away from computers repairing themselves. Let us now consider computer logics. Do “they” have the capability of handling complex thought processes like human ones? Almost! Introduction to Computers 32 An Example – Man Machine Practical Application In 1998, a technology entrepreneur in northeastern Washington was implanted wtih a Radio Frequency Identification (RFID) chip into his hand in order to experiment with the technology. The chip and supporting computer technology was used to gain keyless entry to his car and home, turn on lights, logon to his and other remote and repetitive applications. The experiment was successful and led to other applications for RFID technology.. An implantable RFID chip is a minuscule capsule containing a microchip and an antenna, all enclosed in glass. The chip is about the size of a grain of rice. RFID chips work by storing a unique identification number in the microchip. This number can be retrieved by a special RFID reader that is held within close proximity. Today there are most often implemented in animals to track their whereabouts and to include owner information that can be retrieved by a scanner used by a vet or other animal agency Although RFID technology is relatively old, it is still considered a controversial technology. Privacy advocates fear that the technology might be abused by governments and used to track people. Microchip implants have been used for years for tracking lost pets. Further European research in the area was recently dealt a blow when the European Group on Ethics in Science and New Technologies made a presentation to the European Union raising privacy concerns over the potential for such chips to be used to track members of the public. When employing different technologies we must be aware of not only the technical issues, but issues of privacy, morality, society norms and ethical practices. TOPIC SUMMARY This topic discussed the impact of technology on society. It demonstrated that ICT and computer technologies are an integral part of everyday life. It drives our businesses, entertains us, educates us, and helps ensure our health and wellness. As an entrepreneur you must stay abreast of technological innovations. You must consider how they can help you do your business and more importantly how you can use them to support or create new products and services. Introduction to Computers 33 UNIT 1 SUMMARY After reviewing this unit, reading the suggested articles and exploring the different links you should have concluded that: It seems that computer technology is largely responsible for the ‘emergency’ attitude of modern society. The perception that everything must be done faster, arrive sooner, or be available immediately has pushed services and information to be frequently available on a 24-hour basis. With computer technology, the types of negative impacts and the number of people directly affected by a single system error has grown enormously to where millions can be directly affected. There is unprecedented accessibility to information and communications, available to large numbers of people from nearly anywhere we happen to be. A computer is a machine which accepts data (called input), follows instructions given on what to do with the data (called processing), stores the results for future use (called storage) and displays the results (called output). The main role of computers and computer technology is the ability to manipulate data into information Computer technology is ubiquitous, or (almost) everywhere. Computer technology has enabled us to access information at our ‘finger tips’, from many places, in many places, at any time, and in many different forms whether printed or stored. Information can be retrieved in many forms such as text, voice, graphics, and video Computer technology has allowed surveillance to be made easier with the additional software that can monitor locations in other countries. Computer technology has changed the way we communicate with another person or among groups of people Computer technology can improve our lives in health and medicine such as research in cures for diseases Teleconferencing provides opportunities to have a conference without all persons having to be in the same room, city or country Telecommuting allows employees to work at home and communicate with the office by methods such as phone, fax and computer. Introduction to Computers 34  Telemedicine involves telecommunications, where medical personnel and the patient are separated by some physical distance Expert systems perform tasks that would otherwise be performed by someone with expertise in the field Databases are now used to store dental records, x-rays, medical, insurance and other records for searches and purposes of cross referencing Computer technology has not completely replaced previous inventions; rather it is enhancing and improving on previous ones Businesses have felt most of the impact of computer technology, such that if there is little technology incorporated then the business may be frowned upon as being ‘not-up-to-date’ or archaic. Internet relay chat (also known as messenger), is a common method of chatting with someone either next to you in class, or is a local phone call away Many of us cannot live without having some form of computer technology in our lives This unit introduced the general ideas associated with the impact of technology on different sectors of our society. Are you explored these impacts, you should have noted that they range from the practical and necessary to what may be regarded as leading edge or radical. However in all eras of human history, (a subtle change from ‘revolution’, as in the Industrial Revolution!), our different societies have been faced with change in almost every aspect of their life. This change has been accelerated by the intervention and adoption of computer technologies. It is hoped that this unit caused you to reflect upon the advantages and disadvantages of technology and how it impacts all of us. Introduction to Computers 35 UNIT 2: COMPUTER HARDWARE INTRODUCTION This unit discusses the evolution of computer hardware, provides an introduction the basic components of computer system and explains how a computer processes data that executes different computer instructions. UNIT OBJECTIVES At the end of this unit, you should be able to: 1. Explore the history and evolution of computer technology. 2. Explain the events that occurred in different the computer generations 3. Evaluate the various types of computer systems that have evolved since 1985. 4. Describe the basic components of a computer system. 5. Explain how a computer processes data. This unit is divided into three topics: Topic 1: The Evolution of Computer Technology Topic 2: Computer Hardware and Peripherals Topic 3: Computers and Computing Topic 4: Data Processing Introduction to Computers 36 TOPIC 1 – THE EVOLUTION OF COMPUTER TECHNOLOGY INTRODUCTION Today many jobs mainly depend on the either the creation or collection, and distribution of information. This topic addresses the different advancements in computer technology and the various types of computers and their critical components. OBJECTIVES After studying this topic, you will be able to: 1. Describe the major developments in each generation of computer development. 2. Evaluate the need for different types of computer systems COMPUTER GENERATIONS As each new computer generation improves on its previous generation, there have been a corresponding reduction in size (or miniaturization) of computer circuitry. In contrast to this miniaturization, the speed, power, and memory of computers have proportionally increased. Although this Topic will describe the major developments of each computer generation, it is more important to consider how the technology has influenced the development of current computer systems. The computer generations are summarized in Table 2.1 below: Generation Denoted by Approximate range of years 1 Vacuum tube 1940s- 1950s 2 Transistor Mid 1950s – early 1960s 3 Integrated circuit Early 1960s – Early 1970s 4 Very Large Scale Integration/Microprocessor Early 1970s – Mid 1980s 5 Parallel processing Mid 1980s – Early 1990s 6 Reduced Instruction Set Chip (RISC) and more Mid 1990s to Present inventions to date Introduction to Computers 37 THE FIRST GENERATION COMPUTER (1940S-1950S) Vacuum Tubes These early computers comprised huge vacuum tubes (similar to light bulbs) whose main purpose was to strengthen weak signals for transmission. The vacuum tubes acted as switches to start and stop the instant flow of electricity. The concept underlying the on/off switch was the idea of ones and zeros. The combination of ones and zeros or on and off created a type of machine language that could be used to process information. The first computer, the Mark 1, was so huge that it filled a typical stadium field and was said to have used more than 500 miles of wire. Its success however was its processing power, such as a mathematical problem that normally took 40 hours to solve, only took the Mark 1, 20 seconds to produce a result. It was used by the U.S. Navy during World War II, to help solve strategic military mathematical problems such as cracking secret codes and creating complex fire tables for naval guns and artillery. Scientists used the computer to predict weather patterns and for analyzing problems in airplane design. As noted earlier the language of this first generation was called machine language, which comprised zeros and ones for programming the computer. The next computer, the ENIAC (Electronic Numerical Integrator and Computer) was an improvement on the Mark 1, since its processing power was about 1,000 times faster. The ENIAC was about 80 feet (24.4 m) long by 3 feet (0.9 m) wide, and used about 18,000 vacuum tubes. Unfortunately, the tubes were very hot, had to be replaced frequently, and were costly in using much electricity to keep them cool. The UNIVAC (Universal Automatic Computer) soon replaced the ENIAC by containing a compact 5000 tubes, a reduction from the 18,000 used in the ENIAC. The Second Generation Computer (Mid 1950s – early 1960s) Transistors During this generation the significantly smaller transistors (a new technology) eventually replaced vacuum tubes as the processing component of the computer. This allowed engineers to dramatically reduce the size and space needed to house a computer. Transistors proved to be cheaper to produce and emitted no heat, thus reducing the costs of manufacturing and making the technology more reliable since they conducted electricity faster vacuum tubes and failed less often. This generation was noted for making space travel possible, and for the development of more sophisticated programming languages that allowed programmers to use short specific terms (e.g. ADD) to represent certain computer processing instructions. Higher level programming languages such as FORTRAN, ALGOL and COBOL, which use short English-like words, were developed during this generation. During this generation computer hardware Introduction to Computers 38 and software was created that allowed users to store and retrieve programming instructions. The Third Generation Computer (Early 1960s – Early 1970s) Integrated Circuits This generation improved on the previous one by miniaturizing the transistor and building several onto a single chip of silicon. This compacting of millions of transistors in a small space, also called an integrated circuit, greatly increased the power of computer, the processing speed, lowered its production costs even more and reduced the size of the computer. During this generation the creation of new input and output devices were created. Keyboards, monitors, and the mouse made the computer a more user friendly environment and eliminated the need for huge stacks of punch cards to input data into a main frame computer. Output of the computer calculations could be read on screen vice printing out large amounts of paper with graphic symbols on them The Fourth Generation Computer (Early 1970s – Mid 1980s) The Microprocessor Again an improvement on the previous generation, this generation continued to reduce the size of the silicon chip comparable to the size of a pencil eraser while vastly increasing its computational speeds. This single chip with the components and processing speeds of a computer was called a micro-processor and was initially intended for use in calculators, not computers. During this generation the silicon chip technology was harnessed by the chip manufacturer Intel. Intel in partnership with IBM created the first microcomputer, or personal computer. A few years later Apple in partnership with Motorola introduced the Macintosh to compete against the IBM personal computer. Only recently has Apple recognized the need for standardization and has embraced the Pentium technologies currently supported by Intel. During this periods new and more powerful programming languages developed. This included Pascal, C and compilers which converted the program to a lower level language that the machine could process. The UNIX operating system was also developed during this time to manage system resources. Introduction to Computers 39 The Fifth Computer Generation Computer (Mid 1980s – Early 1990s) Artificial intelligence and Parallel Processing The goal of this generation is to develop devices that are capable of responding sensibly to a user’s natural language and also capable of learning and self-organization. It is characterized by the introduction of computers with hundreds of processors that could be assigned to work on different sections of a single program. This is called parallel processing, and is being used to develop communication between a computer in natural spoken language and its user, through access to a vast knowledge database to make intelligent inferences and draw logical conclusions in the way that humans do. Several programming languages known as artificial intelligence (AI) languages have been developed simply because they are used almost exclusively for AI applications. The two most commonly used languages are LISP and Prolog. The linking of computers together, called computer networks, and the increasing use of workstations (explained in table 2.1) were also developed during this generation. Activity 2.1 - Consider the advantages and disadvantages of the development of artificial intelligence in this generation Turn to Appendix One for Suggested Response The Sixth Generation (Mid 1990s to Present) Computers and Video Games This era refers to the generation of computer and video games which became popular around 1998. The Nintendo Game Cube, Sony PlayStation 2, and Microsoft's Xbox are noted to have dominated game playing in all age groups. Introduction to Computers 40  Figure 2.1: General Timelines of Computer Generations G6: Game Playing G5: Parallel G4: Microprocessor G3: Integrated Circuit G2: Transistor G1: Vacuum Tube 1940 1950 1960 1970 1980 1990 2000 2010+ Years Activity 2.2 – Reflect upon what facilitated the increase in speed, power or memory in each of the computer generations. Turn to Appendix One for Suggested Response Types of Computer Systems In the past computers were classified as microcomputers, minicomputers, or main-frame computers, based on their size. Today these distinctions are rapidly disappearing as the capabilities of even the smallest units rival that of their earlier big brothers. Today’s microcomputers are faster, more powerful and more versatile than the minicomputers and the main-frame computers were a few years ago. Table 2.X describes the terms used to classify today’s of computers and computing devices. Type of Brief Description Computer System Desktop Computer A PC that is expected to be placed on the top of a computer or other desk. Desktops usually are powerful and have reasonably large secondary storage. Desktops require a number of input and out devices to make them useful. Laptop Compared to the desktop, laptops are portable computers that have their monitor, keyboard, and other memory and storage devices all included in a packages that is up 17 inches in size and is powered by a special battery. Laptops are also called notebooks. Introduction to Computers 41  Type of Brief Description Computer System Mainframe Mainly associated with large companies, that process millions of transactions calculations from multiple sources at one time, mainframes previously filled large rooms, but today consist of a number of linked components that allow the different processors to communicate with one another and share their total computing power. Minicomputer Minicomputers are powerful and can support many users at once. Their size is between microcomputers (PCs) and mainframes. Palmtop More commonly called Personal Digital Assistants (PDAs). They are compact computers that often use special secondary flash memory instead of a typical hard drive for storage. Palmtops usually have optional keyboards but mainly use touch screens for input. They are typically the size of a paperback novel or even smaller and are very lightweight and use battery power. Personal Computer Personal Computers (PC) was designed to be used by individuals for general use. The PC is not usually associated with the Apple Mac although it is a PC. Often the term desktop and PC are used interchangeably. Server A computer that has been optimized to provide services to other computers over a network. Servers usually have powerful processors, lots of memory and large hard drives. They often provide custom services such as an e-mail server, a backup server, a database server, etc. Supercomputer Supercomputers have the world’s fastest processors and are able to perform millions of computations a minute. Supercomputers are normally comprised of multiple high performance computers working in parallel as a single system. The best known supercomputers are built by Cray Supercomputers. Wearable This is the latest trend in computing where common computer computers applications such as electronic mail, are integrated into watches, cell phones, visors and even clothing. Workstation A workstation is a desktop computer with a more powerful processor, and more memory for performing a special functions, such as 3D Graphics Introduction to Computers 42  Activity 2.3 - Explain, with reasons, which computer system(s) would be most appropriate in the following examples: 1. Business executive who travels often 2. Student who needs to prepare a History project report 3. A multi-million dollar company with six branches in the country and three in other countries 4. Banking system with many tellers who access the same customer database Turn to Appendix One for Suggested Response TOPIC SUMMARY Since the 1940s when computer technology was used to support the creation of firing tables for the artillery and to the introduction of the World Wide Web network of computers in the 1980s computer technologies have become a large part of our everyday life. The use of computers is accelerating. They are now in our cars, our phones, our refrigerators. Almost every type of electronic device has a computer chip in it. Each chip relays on commands. Commands must be input using different devices. The next topic will examine some of these input and output devices. Introduction to Computers 43 TOPIC 2 – COMPUTER HARDWARE AND PERIPHERALS INTRODUCTION This topic presents a brief discussion on computer and their components and other basic concepts you need to familiarise yourself with before using the computer. OBJECTIVES Upon completion of this lesson you will be able to: 1. Distinguish between different hardware components of a computer. 2. Explain the functions/uses of the different components. We have briefly looked at the different types of computer systems in Topic 1. We will discuss the different hardware components that make up different computer systems. The hardware and peripherals can be categorized as either Input, output, process or storage devices. INPUT DEVICES You use input devices to provide information to a computer, such as typing a letter or giving instructions to a computer to perform a task. Some examples of input devices are described in the following list. Mouse: A device that you use to interact with items displayed on the computer screen. A standard mouse has a left and a right button. Trackball This is an alternative to the traditional mouse and is favoured by graphic designers. It gives a much finer control over the movement of items on the screen. Other screen pointing devices are pointing stick, touch pad, joystick, light pen, digitizing table. Keyboard: A set of keys that resembles a typewriter keyboard. You use the keyboard to type text, such as letters or numbers into the computer. Introduction to Computers 44  Scanner: A device that is similar to a photocopy machine. You can use this device to transfer an exact copy of a photograph or document into a computer. A scanner reads the page and translates it into a digital format, which a computer can read. For example, you can scan photographs of your family using a scanner. Barcode Readers: When used in a business barcodes provide a lot of information. Made up of columns of thick and thin lines, at the bottom of which a string of numbers is printed. Multimedia devices This is the combination of sound and images with text and graphics. To capture sound and image data, special input devices are required. Microphone: Voice input, for instance, can be recorded via a microphone. A device that you can use to talk to people in different parts of the world. You can record sound into the computer by using a microphone. You can also use a microphone to record your speech and let the computer convert it into text. Webcam: A device that is similar to a Digital cameras record photographs in video camera. It allows you to capture the form of digital data that can be and send the live pictures to the other stored on a computer. These are often user. For example, a webcam allows your used to record photographs on identity friends and family to see you when cards. communicating with them. Take a few minutes to reflect on the content discussed so far. Self-Reflection Activity Look around in your immediate environment (shops, government institutions, at home, etc) and see if you can recognise any of the above discussed input devices. Can you remember Introduction to Computers 45 the functions of each of the devices that you have identified? Let’s continue our discussion by looking at the second type of computer hardware. OUTPUT DEVICE Output devices in the computer system are the equipment whereby the result of a computer operation can be viewed, heard or printed. You use output devices to get feedback from a computer after it performs a task. Some examples of output devices are described in the following list. Monitor: A device that is similar to a television. It is used to display information, such as text and graphics, on the computer. Printer: A device that you use to transfer text and images from a computer to a paper or to another medium, such as a transparency film. You can use a printer to create a paper copy of whatever you see on your monitor. Plotter: A plotter is an output device similar to a printer, but normally allows you to print larger images. It is used for printing house plans and maps. Multimedia Output Device: The most common multimedia output is sound, including music. The audio output device on a computer is a speaker. Headphones can also be used to receive audio output. Take note One of the things that you need to make sure of is that you get the right printer. How do you know what printer to get? There are various types of printers available and these vary considerably in the quality of their production. Introduction to Computers 46 Impact Printers Dot matrix printers are an example of impact printers. They form characters from patterns of dots. They are inexpensive, but the output can be difficult to read. Non-impact Printers Inkjet printers work by shooting a jet of ink in the shape of the character required, they provide god, low-cost colour printing. Laser printers – a laser beam is directed at an electro-statically charged surface, creating a template of the page to be printed. This template is then used to transfer the ink to the page. Toner sticks to the light images and is transferred to paper. PROCESS AND STORAGE DEVICES The system unit is the name given to the main computer box that houses the various elements as illustrated in the picture below. CPU Motherboard Extension cards Drivers Connection ports How do we get the different computer parts to work together so that your computer can work? Let’s start of our discussion with the process devices. Introduction to Computers 47 Motherboard Inside the systems unit is a circuit board with tiny electronic circuits and other components which is called a mother board. It is sometimes called a system board. The motherboard connects input (keyboard, mouse and scanner), output (monitor, speakers, and printer), processing (CPU, RAM and ROM) and storage (hard drive, CD-ROM/DVD-ROM and flash drives) components together and tells the CPU how to run (Lubbe and Benson, 2010:18). Other components on the motherboard include the video card, the sound card, and the circuits that allow the computer to communicate with devices like the printer. Expansion Cards Yes you can play music and video files on your computer. But how is it possible? Inside the computer system box you also find an expansion card which is another circuit board that can be attached to the motherboard to add features such as video display and audio capability to your computer. Expansion cards are also called expansion boards that enable your computer to use the multimedia devices. An expansion card either improves the performance of your computer or enhances its features. Examples of expansion cards that can be added include: Video Card: It is connected to the computer monitor and is used to display information on the monitor. Network Interface Card (NIC): Remember we’ve explained computer networks in Unit 1. The NIC allows the computer to be connected to other computers so that information can be exchanged between them. Sound Card: It converts audio signals from a microphone, audio tape, or some other source to digital signals, which can be stored as a computer audio file. Sound cards also convert computer audio files to electrical signals, which you can play through a speaker or a headphone. The microphone and the speakers or the headphones connect to the sound card. STORAGE DEVICES All computers need to store and retrieve data for processing. The CPU is constantly using memory from the time that it is switched on until the time you shut it down. There are two types of storage devices as illustrated in the flow chart below. Introduction to Computers 48 Primary Storage is also called main memory or immediate access store (IMAS). This is necessary since the processing unit can only act on data and instructions that are held in primary storage. Primary storage consists of two types of memory chips: Random Access Memory (RAM) Read Only Memory (ROM) Random Access Memory (RAM) is the main working memory. RAM is only filled after a computer has been turned on and is given something to do. It holds data and instructions temporarily while processing takes place. RAM is volatile – this means that if the power is turned off or the computer reboots (start up again) all the information held in RAM will be lost. RAM is measured in MB (megabytes) and most entry level computers will have 1024 MB RAM but you also find some computers having up to 3 GB RAM. RAM chips are expensive and the price of a computer is determined by the amount of RAM space in the chip. Read Only Memory (ROM) holds data and instructions necessary for starting up the computer when it is switched on. These instructions are hard-wired at the time of manufacture. ROM is permanent and cannot be deleted but can only be accessed or read, hence the name Read Only Memory. Data stored in ROM is non-volatile – meaning that memory will not be lost when power is turned off. Introduction to Computers 49 So we can compare the features of the two memory types as below: Fig. 2.1 Comparing RAM and ROM RAM ROM Needs power Does not need power Data can be changed Data can’t be changed Data will be lost if power is turned off Data will not be lost if power is turned off Volatile Non-volatile Stores data currently being processed Fixed instructions is stored [Source: Lubbe and Benson, 2010:20) Units of Storage The memory of all digital computers is two-state (bi-stable) devices. Computers operate using a binary number system – and therefore use binary digits (bits). Bits have only two values by 0 and 1. A bit is the smallest unit of storage in a computer. The amount of data and instructions that can be stored in the memory of a computer or secondary storage is measured in bytes. A byte is made up of a combination of eight (8) bits and has the storage power to represent one character (a character is a letter or symbol or punctuation mark or blank space). Units of Storage 1 byte 8 bits 1 kilobyte (K) 1024 bytes 1 megabyte (MB) 1000 kilobytes (approx. 1 million bytes) 1 gigabyte (GB) 1000 megabytes (approx. 1 billion bytes) 1 terabyte (TB) 1000 gigabytes (approx. 1 trillion bytes) Secondary Storage Devices PCs use a simple method of designating disk drives to store data. These drives are assigned letters of the alphabet. Introduction to Computers 50  A Drive Floppy drive. Still found in older computers C Drive Internal hard drive (hard disk drive) situated inside the system case. D Drive Usually the CD-ROM/DVD-ROM driv