N4 Computer Practice PL Immelman Student s Book TVET FIRST NATED SERIES
N4 Computer Practice Student s Book PL Immelman
Computer Practice N4 Student s Book PL Immelman, 2012 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, photocopying, recording, or otherwise, without the prior written permission of the copyright holder or in accordance with the provisions of the Copyright Act, 1978 [as amended]. Any person who does any unauthorised act in relation to this publication may be liable for criminal prosecution and civil claims for damages. First published in 2012 by Troupant Publishers [Pty] Ltd PO Box 4532 Northcliff 2115 Distributed by Macmillan South Africa [Pty] Ltd ISBN: 978-1-4308-0002-6 Web PDF ISBN: 978-1-4308-0219-8 It is illegal to photocopy any page of this book without written permission from the publisher. Acknowledgements Microsoft product screenshots used with permission from Microsoft. While every effort has been made to ensure the information published in this work is accurate, the authors, editors, publisher and printers take no responsibility for any loss or damage suffered by any person as a result of reliance upon the information contained herein. The publisher respectfully advises readers to obtain professional advice concerning the content. While every effort has been made to trace the copyright holders and obtain copyright permission from them, in some cases this has proved impossible due to logistic and time constraints. Any copyright holder who becomes aware of infringement on our side is invited to contact the publisher. Note: Any reference to Further Education and Training (FET) in this book should be taken to mean Technical and Vocational Education and Training (TVET). To order any of these books, contact Macmillan Customer Services at: Tel: (011) 731 3300 Fax: (011) 731 3535 E-mail: customerservices@macmillan.co.za
Contents MODULE 1 INTRODUCTION TO COMPUTERS 1 Unit 1.1 What is a computer?...1 Unit 1.2 Hardware and software...4 MODULE 2 KEYBOARD PROFICIENCY 12 Unit 2.1 The Keyboard...12 Unit 2.2 Correct sitting posture...13 MODULE 3 SYSTEM SOFTWARE 24 Unit 3.1 Magnetic storage media...25 Unit 3.2 Files and file names...27 Unit 3.3 The operating system...28 Unit 3.4 My Computer...37 Unit 3.5 Formatting...37 MODULE 4 TEXT MANIPULATION 43 Unit 4.1 Word processing...43 MODULE 5 TEXT MANIPULATION (2) 57 Unit 5.1 Special print functions...57 Unit 5.2 The Help menu...71 MODULE 6 TEXT MANIPULATION (3) 73 Unit 6.1 Formatting...73 MODULE 7 TEXT MANIPULATION (4) 116 Unit 7.1 Working with text...116 MODULE 8 TEXT MANIPULATION (5) 130 Unit 8.1 Headers and footers...130 MODULE 9 SPREADSHEETS (1) 170 Unit 9.1 How to start up Excel...170 Unit 9.2 Types of entries...174 MODULE 10 SPREADSHEETS (2) 193 Unit 10.1 Columns...193 MODULE 11 SPREADSHEETS (3) 214 MODULE 12 SPREADSHEETS (4) 236 GLOSSARY 256 iii
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MODULE 1 INTRODUCTION TO COMPUTERS OVERVIEW At the end of this module, you should be able to: Identify different fields of computer applications in the business world. Differentiate between different types of computers. Identify the different parts of a microcomputer. Explain why a computer needs an operating system and differentiate between systems and applications software. Identify the different hardware components of a computer system. Differentiate between output and input peripherals. Explain why a computer system needs memory and differentiate between ROM and RAM memory. Compare printers. Differentiate between and explain the uses of the different peripherals. UNIT 1.1 WHAT IS A COMPUTER? A computer is a set of integrated components that process data according to instructions. It is an electronic device that carries out arithmetic and logical processing according to a program (a list of instructions telling the computer what to do). A computer processes data accurately at high speed and can save great quantities of data in its memory, hard drive, flash disk or on CDs. A computer can also retrieve processed data from flash disks or CDs. Data: information processed by a computer Program: a set of instructions or code the CPU executes, designed to help you solve problems or perform tasks, also called software Hard drive: a piece of hardware in the computer case that permanently stores large amounts of information Flash disk: a small, ultra-portable storage device which, unlike a hard drive, has no moving parts. Most flash drives connect to the PC via a built-in USB port CD: (compact disk) is a type of medium used to store files and information The development of computers Long ago, people used sticks and stones to count. They carved marks into pieces of bone and wood and they made knots on pieces of string to keep records. The abacus, which originated in China, was the first step in the development of computer technology. The development of generations was recognised by the time the computer was developed. Tubes and valves were used by the first generation. Transistors were used in the second 1
generation to make computers smaller and faster. The integrated circuit defined the third generation. The memory and the microprocessing chip started the microcomputer of the fourth generation. The latest technology continues to produce microcomputers with more memory, speed and power. Computer applications Computers play an essential role in the business world. Today it would be impossible for a business to work effectively without them. The following are common applications of computers in the business world. Word processing Word processing is the manipulation of text. You can type information and save it on the hard drive or flash disk or a CD for later use or to be modified and corrected. Word processing programs include Microsoft Word and Microsoft Word Pad. Spreadsheets A spreadsheet program manipulates numbers and does mathematical calculations. You can also use formulae in a program like Microsoft Excel or Lotus 1-2-3. Accounting Different transactions can be entered into the computer in a specific accounting program and neat and accurate results will be available for decision-making by management. Income statements, balance sheets, stock control, turnover and budgets are only a few options a program such as Microsoft Pastel offers. Desktop publishing and graphics Microsoft Publisher, for example, can be used to design books, newspapers, magazines or graphics. Database This is a type of filing system, such as Microsoft Access, used at schools, colleges, universities and companies for processing the personal details of students and personnel. Even video shops can use the database for the videos available in their shop. Application: a program in which you do your work Spreadsheet: a program designed to look like an electronic ledger Types of computers There are various types of computers. Some include mainframe computers, super computers, microcomputers and laptop computers. Mainframe computers These are huge and powerful computers used by large companies, for example, call centres, commercial banks and export and import companies. These computers 2
terminals are linked to the main computer. The terminal consists of a monitor, a keyboard and a printer. Figure 1.1 A mainframe computer and a laptop computer The main computer has multiple access arms with read and write heads capable of serving more than one terminal at a time. It has a large storage capacity of millions of characters (gigabytes) and can process a huge amount of information fast. These computers need air-conditioned, dust-free rooms and are online 24 hours a day. Specially trained staff need to operate them. Supercomputers Supercomputers are more powerful and faster than mainframe computers. They are also more expensive and only used by very large institutions. Minicomputers These are smaller versions of mainframe computers to which a limited number of terminals can be linked. They are cheaper, slower and have less storage capacity than the mainframe computer. Microcomputer setup The microcomputer consists of a central processing unit (CPU), a mouse and keyboard, a visual display unit (VDU) and a printer. Smaller businesses use microcomputers for ordinary data processing, for example, accounting, salaries, wages, word processing and stock control. Only one operator uses the microcomputer and it has no extra terminals. It is driven by a powerful microprocessing chip. Monitor: an output device that looks like a TV screen, also called the computer screen Keyboard: most common input device, used to enter letters, numbers, symbols, punctuation and commands into the computer Printer: a piece of equipment that creates a hard paper copy of the input as it is seen on the computer screen Gigabytes: (GB) 1024 megabytes CPU: the central processing unit or brains of the computer, which interprets and executes program instructions Microcomputer: a complete computer on a smaller scale, generally a synonym for a personal computer or PC 3
Assessment activity 1.1 (Individual) 1. List the advantages and the disadvantages of using a computer rather than doing everything manually. 2. In table form, compare three types of computers and three characteristics of each type. 3. Name the different parts of a microcomputer. 4. Mention the uses of computers in the business world. UNIT 1.2 HARDWARE AND SOFTWARE The microcomputer consists of two main components, namely hardware and software. Figure 1.2 Hardware and software Software The software refers to the part of the computer that cannot be seen or touched. Without the software programs, the computer hardware cannot operate. Software consists of programs. A program is a set of instructions in computer language, which tell the computer what to do and how to perform an action. Software or programs are divided into two different sections: System software The system software contains all the primary elements of software no other software can be used without it. System software provides the instructions that run the computer. Systems software is also called the operating system. The operating system controls the internal management of the computer. Examples of system software are MS DOS, Windows 98, 200, 2007, XP, NT, UNIX and LINUX. Applications software This is specialised software written to execute specific tasks. Microsoft Word, for instance, is used to type documents such as correspondence. You can do arithmetical calculations using Microsoft Excel. An auditing company will use Softline Pastel for budgets, income statements and balance sheets. 4
Language systems Programmers use language systems to write programs, for example, Pascal, Basic and C. Hardware The hardware of a computer consists of those parts that you can see and touch, including devices that can be attached to the computer and the CPU. Examples of these devices are modems, keyboards, disk drives, printers and mouses. Hardware components CPU The CPU is referred to as the brain of the computer. It coordinates and supervises the operation of the input, memory, output and Arithmetic Logic Unit of a computer. All the information is first translated into 0s (on) and 1s (off) (or binary codes) for the computer to manipulate. This is because the computer processor cannot work with letters, figures or words. The memory storage capacity of a computer (in other words, the space on the computer) is measured in bits and bytes. 1 bit = 1 binary number 0/1 8 bits = 1 byte (8 bits is a unit of information) 1024 bytes = 1 kilobyte 1 million bytes = 1 megabyte 1024 megabytes = 1 gigabyte Operating system (OS): needed to make computer programs work. Operating systems perform basic tasks, such as recognising input from the keyboard or mouse, sending output to the computer screen, keeping track of information stored on disk drives, and controlling hardware such as printers. Document: a file that has been created in an office program, such as word processing or spreadsheet Modems: devices that connect a computer to the internet through a telephone line Bit: the smallest piece of information used by a computer, in computer language, either a 1 or a 0 Byte: a piece of computer information made up of 8 bits Input device: computer hardware that accepts data and instructions, such as the keyboard and mouse Output device: a hardware component, such as a monitor or printer, that returns processed data Arithmetic Logic Unit: the part of a CPU that performs mathematical operations The CPU consists of the following parts: The control unit This unit controls the computer s input and output devices. It also loads and stores data to and from the computer and it controls the flow of information between the main memory and the Arithmetic Logic Unit. 5
The Arithmetic Logic Unit (ALU) This unit is responsible for the arithmetic calculations such as adding, subtracting, multiplying, dividing and comparisons. Read Only Memory (ROM) The ROM is the permanent memory of the computer. It contains the instructions to start the computer. The data/information on the ROM can only be read and cannot be deleted or changed. The computer uses the ROM to read the circuit boards and to check the peripherals of the computer. Information necessary to make the computer run smoothly is stored on the ROM during the manufacturing process. Random Access Memory (RAM) The RAM is the temporary memory of the computer. It is used to save data and programs during processing. The RAM of the computer will be erased when the computer is switched off. It also defines the size of your computer, for example,16mb, 32MB. Programs used during processing and data entered via the keyboard are stored in the RAM. Information or data can also be transferred from the RAM to a flash disk or CD. Peripherals All other attachments to the computer are called peripherals. These devices are either used to send information to the computer or to receive information from the CPU. The terms input and output devices are used for these functions. Input Keyboard (communication) Disk drives Mouse Modem Joystick Lightpen Output Printer (hard copy) Visual Display Unit (VDU or screen) Plotter Scanner Voice recognition devices ROM (Read Only Memory): a computer s built-in memory containing data that can normally only be read and not written to. ROM contains the programming that allows the computer to be booted up Peripherals: devices connected to a computer, but not part of it, such as a mouse or keyboard RAM (Random Access Memory): a computer s temporary memory. RAM stores data and programs while they are being used MB: Short for megabyte or 1024 kilobytes, used to measure the size of a computer s memory 6
Assessment activity 1.2 (Individual) 1. Define hardware and software. 2. Differentiate between application software and system software. 3. In a diagram, show the computer system, the input and output devices as well as the CPU and the different memories. 4. List the functions of the CPU and name its parts. 5. Differentiate between the RAM and the ROM of a computer. Components of a computer system CPU (central processing unit/the brain of the computer) Arithmetic Logic Unit The primary memory ROM (read only memory) RAM (random access memory) Output Diskettes Printer Visual display unit Fig 1.3 Components of a computer system 7
Keyboard The keyboard is used for communication between the computer and the Visual Display Unit (VDU or screen). All the information that you key in will be displayed on the VDU. Figure 1.3 A keyboard Visual Display Unit The screen is similar to the screen of a TV except that you can see the text you type on the screen. It is the communication device between the operator and the computer. Make sure that you read the information on the screen because it is the only way that the computer can communicate with you the operator. Types of VDUs Monochrome screens These screens cannot display colours. The background screen is black with white, green or amber characters. Figure 1.4 A VDU Colour screens These screens can display different colours in different resolutions. Colour can also convey information. Resolution is measured in the number of horizontal and vertical pixels (dots). Pixels make up graphics. Various types of adapters are available for colour screens. EGA and CGA (Enhanced/Colour Graphics Adapter) It displays text and graphics in colour. VGA (Video Graphics Adapter) It has more colours, but is otherwise the same as the EGA. Super VGA This screen is very sophisticated and displays more than 256 colours. Sizes of VDUs Screens come in different sizes from 14 inch to 20 inch. To reduce eye fatigue, try to use a 15 inch screen. You should be able to see 80 characters horizontally and 24 lines vertically on the screen. You can adjust the brightness and contrast with the buttons on the screen. How to reduce eye fatigue The recommended screen size is 14 inches (288 mm) to 15 inches (355 mm) horizontally. This will not cause eye strain with characters that are too small and require too much 8
eye movement. Keep your eyes the correct distance from the screen or about 30 inches or 621 mm away from the screen (two screen lengths). The correct reading angle is 10 to 15 degrees or just below the horizontal viewing line. You can adjust your chair to ensure the correct reading angle. You can use overhead lighting to avoid reflection on the screen. Also avoid reflection of light from doors and windows. Try not to strain your eyes for more than an hour at a time. Rest your eyes after an hour. Intensive full-time work on a computer makes heavy demands on the eyes and can cause headaches, blurred vision and double vision. Go for regular eye tests. Printers Printers are divided into two main groups: impact and non-impact printers. Figure 1.5 Eye fatigue must be avoided Impact printers Dot matrix printers These printers are used for general office work and work on the principle of eight straight pins in a line. They can print text and graphics and a variety of letter types. They are cheaper and faster than daisy wheel printers. The letter quality is not outstanding, but you can use the near letter quality (NLQ) function. Daisy wheel printers They work on the principle of a round disk with spokes, with characters attached on the end of each spoke. The wheel rotates to find the desired character. This impacts on the ribbon and then onto the paper to print the required characters. Daisy wheel printers cannot print graphics or a variety of letter types. They are slow and more expensive than dot matrix printers. They give a high letter quality and are usually used for word processing. Non-impact printers Figure 1.6 A dot matrix printer Laser printers Laser printers represent the highest state of printing technology. They include laser imaging, precise paper movement and microprocessor control of all actions. They have 9
fewer moving parts than impact printers. They are faster, easier to use and less noisy than impact printers. You do not have to change ribbons or daisy wheels. Laser printers can print text and graphics with a variety of letter types. A high quality of printing is produced. They are expensive to buy, but save time and increase efficiency. Ink jet printers Ink jet printers are becoming more affordable and are being used in the general office environment. The letter quality is good, and a variety of letter types and graphics can be printed. These printers use a print cartridge with black ink which forms the characters. Colour cartridges produce a high quality of colour printing. Ink jet printers can feed paper automatically, adjust to the paper size, and print labels and envelopes which make them a popular printer for general office work. They are userfriendly and printing is fast and quiet. Other peripherals Figure 1.7 A laser printer Mouses The most popular mechanical pointing device is the mouse. You can point to images instead of typing commands. You can use the mouse for application programs using graphic displays (icons) to control the cursor. Figure 1.8 Examples of mouses The mouse has two or three control buttons, which will transfer signals to the software. Old mouses have a moving ball underneath them. When you move your mouse on the mouse pad, the cursor will move on the screen. Lightpens You can use a lightpen to draw images on a flat LCD screen. They are usually used by architects. Joysticks Joysticks are used to move the cursor quickly when playing games. They also have a lever that can move in different directions. Figure 1.9 An old and modern joystick 10
Scanners Scanners, the eyes of a computer, may be handheld or flat-bed. They convert graphics, text, pictures or drawings into a code so that they can be used in a DeskTop Publishing (DTP) program to display the images on your screen. You can also print, edit and save these pictures. Modems Modems make communication possible through two computers via a telephone line. When you use a modem, both computers should be connected to it. Information is transferred from one computer to another via the modem. Plotters A plotter is an output device. It takes the form of a drawing machine connected to the computer and receives impulses from the computer to produce pictures or graphics. Plotters are used to make drawings of dams, roads, buildings and bridges. The plotter works with pens moving across the paper to produce graphics. Voice recording devices These use the human voice and a direct input device. They can only be used once a person s voice is pre-programmed into the computer to be recognisable. Mouse: an input device you roll across a flat surface, used to control the pointer by pointing and clicking, double clicking or dragging objects on the screen Cursor: the pointer, usually arrow-shaped, which is controlled by the mouse Assessment activity 1.3 (Individual) 1. In table form, compare the features of a dot matrix printer, laser printer and ink jet printer. 2. Differentiate between the different types of VDUs. 3. Name five peripherals that could be connected to your computer. MODULE SUMMARY In this Module you: Identified different fields of computer applications in the business world. Differentiated between the different types of computers. Identified the different parts of a microcomputer. Learnt about an operating system and the difference between systems and applications software. Identified different types of hardware components. Learnt about output and input peripherals and compared printers and about the uses of different peripherals Explained the need for computer memory and the difference between ROM and RAM memory. 11