Chapter 1 : Introduction to Computer & Information Technology

Transcription

1 Chapter 1 : Introduction to Computer & Information Technology 1.1 Characteristics of a Computer 1.2 Definitions 1.3 Basic Elements of Computer System 1.4 Computer Tasks Components of Computer System 1.5 Uses of Computer systems Use of Computers in Education Uses of computer in business Uses of Computers in Hospitals 1.6 History of Computers& Computer Generations FIRST GENERATION: (The Vacuum Tube Era) SECOND GENERATION: (The Era of the Transistor) THIRD GENERATION: ( Miniaturizing the Computer ) FOURTH GENERATION: over 1971 (The Microprocessor Era) FIFTH GENERATION: Updated (super/ultra large-scale integrated circuits Era) Chapter 2 : Computer system components 2.1 Hardware The CPU 2.2 How Computers Store Data Storing Numbers 2.3 Software System Software Application Software 1

2 Chapter 3 : Classification of Computers 3.1 Supercomputers 3.2 Mainframe Computers 3.3 Minicomputers 3.4 Microcomputers 3.5 Personal Computer PC 3.6 Desktop Computer 3.7 Laptops 3.8 Palmtops (Tablets) Chapter 4 : Computer Networks 4.1 Local Area Network (LAN) LAN TOPOLOGIES Linear Bus Topology Star Topology Tree or Expanded Star 4.2 Wide Area Network (WAN) WAN Connection Technology Options Chapter 5 : General Computer Topics 5.1 Computer Crimes 5.2 Computer Viruses Viruses Virus Protection 5.3 Computer Ethics 2

3 Chapter 6 : Introduction to Internet 6.1 Identify each of the ARPANET and the INTERNET 6.2 Basic Internet Definitions 6.3 Introduction to Internet 6.4 What are the Browsers & Search Engines 6.5 What is and How to Use IT 6.6What is Signatures & Signature Files 6.7 Internet Behavior and ETHICS. Chapter 7 : Microsoft Windows 7 Part1 : Getting Started with Windows 7 Fundamentals 7.1 What is Windows 7? 7.2 Previous versions of windows 7.3 What is new in Windows 7? 7.4 What are the improvements in Windows7 than Vista and XP? 7.5 Advantages of Windows Drawbacks of Windows Windows 7 Desktop 7.8 Windows 7 Taskbar 7.9 Quick Launch Icons 7.10 Notification Area 7.11 Windows Aero 7.12 Jump Lists 7.13 Using Command Buttons, Menus, and Dialog Boxes 7.14 A Sample Dialog Box 7.15 Dialog Box Elements Part 2 : Getting Started with Windows 7 Practice and Skills Gaining 3

4 7.16 Personalize the Windows 7 Desktop 7.17 Add and Remove Gadgets 7.18 Add Shortcuts 7.19 Move Between Windows and Customize the Taskbar 7.20 Resize, Move, and Scroll Windows 7.21 Exiting Windows 7.22 Use Windows Explorer and Create Folders 7.23 Move and Rename Folders and Copy Files 7.24 Move, Rename, and Delete Files 7.25 Compress Files and Use the Address Bar 7.26 Explore Your Computer Using Folder Windows 7.27 Describe and Find Files and Folders 7.28 Create Backup Copies of Your Work 7.29 Use Libraries to Organize Files 7.30 Capture a Screen with the Snipping Tool 7.31 Organize Files 7.32 Search and Preview Files 7.33 Delete and Restore Files Chapter 8 : Microsoft Word Microsoft word 2010 interface 8.2 Starting to use microsoft word Text formatting 8.4 Paragraph formatting 8.5 Finding and replacing text 8.6 Page formatting 8.7 Customization 8.8 Proofing and printing 8.9 To encrypt your file and set a password to open it 8.10 How to create a strong password 8.11 Commonly used keyboard shortcuts 8.12 Common tasks 4

5 8.13 Working with documents: create, view, and save documents 8.14 Working with documents: find, replace, and browse through text 8.15 Tables 8.16 Columns 8.17 Styles Chapter 9 : Microsoft Excel Using excel Selection techniques 9.3 Manipulating rows and columns 9.4 Manipulating cells and cell content 9.5 Font formatting 9.6 Alignment formatting 9.7 Number formatting 9.8 Setup & printing issues 9.9 Templates 9.10 Cell formatting 9.11 Freezing row and column titles 9.12 Formulas 9.13 Functions 9.14 Filtering 9.15 Chart basics Chapter 10: Microsoft PowerPoint The Microsoft PowerPoint 2010 screen 10.2 Working with a presentation 10.3 Creating a presentation 10.4 Manipulating slides 10.5 Themes 10.6 Manipulating slides 10.7 Slide shows 10.8 Printing and proofing 5

6 10.9 Graphics Charts Organization charts Slide shows 6

7 Chapter 1 Introduction to Computer& Information Technology In school, students use computers for tasks such as writing papers, searching for articles, sending , and participating in online classes. At work, people use computers to analyze data, make presentations, conduct business transactions, communicate with customers and coworkers, control machines in manufacturing facilities, and do many other things. At home, people use computers for tasks such as paying bills, shopping online, communicating with friends and family, and playing computer games. Computers can do such a wide variety of things because they can be programmed. This means that computers are not designed to do just one job, but to do any job that their programs tell them to do. A program is a set of instructions that a computer follows to perform a task. For example, Microsoft Word is a word processing program that allows you to create, edit, and print documents with your computer. Adobe Photoshop is an image editing program that allows you to work with graphic images, such as photos taken with your digital camera. Programs are commonly referred to as software. Software is essential to a computer because it controls everything the computer does. All of the software that we use to make our computers useful is created by individuals working as programmers or software developers. A programmer, or software developer, is a person with the training and skills necessary to design, create, and test computer programs. Computer programming 7

8 is an exciting and rewarding career. Today, you will find programmers work used in business, medicine, government, law enforcement, agriculture, academics, entertainment, and many other fields. In brief, A computer is a programmable machine. It allows the user to store all sorts of information and then process that information, or data, or carry out actions with the information, such as calculating numbers or organizing words. 1.1 Characteristics of a Computer The Characteristics which make computer indispensable are: 1) Speed: The computer is able to process the date and give the output in few microseconds, in order to enable the user to use such required information on time and take right decisions on right time. 2) Automation: Once the instructions reach the computer, it works automatically without any human intervention until the completion of execution of program and meeting logical instructions to terminate the job. 3) Diligent: The computer performance is consistent even to all extent of more than 10 million calculations; it performs each calculation with same speed and accuracy. Computer is capable of executing about 3 million calculations per second. 4) Accuracy: In spite of its high speed of processing, computer's accuracy is consistently high enough to avoid any errors. If it happens to have errors, they are due to errors in instructions given by the programmer. 5) Reliable: The output generated by the computer is very reliable. This only happens when the data passing as input to the computer and the program, are correct and reliable. 8

9 6) Storage Capacity: The computer has a provision to store large amount of data in the small storage devices, which have capacity to store huge amounts of data and help the retrieval of data an easy task. 7) Versatile: The computer performs three basic operations: It is capable to access and accept information through various inputoutput devices from the user. It performs basic Arithmetic and Logic operations on data as desired. It is capable to generate the desired output in the desired form. Limitation of Computer : 1) Computer does not work on itself; it requires set of instructions to be provided. 2) Computers are not intelligent; they have to be instructed about each and every step to be performed. 3) Computers cannot take decisions on its own, one has to program the computer to take an action if some conditional prevail. 4) Computers, unlike humans cannot learn by experience. 1.2 Definitions In brief, we can say that a computer is an electronic machine that is capable of performing arithmetic & logical operations on an entered set of data, processing it and outputs information that is useful for the user. 9

10 Arithmetic operations: Table 1.1 illustrates the four known math operations. Table 1.1 the four known math operations. Operation In Math In Computer Addition + + Subtraction - - Multiplication * Division / Any other operation, such as square root, sine, cosine, tan and many others can be put in a combination of these main operations Logical operations: Table 1.2 shows the operations that have a result of either TRUE or FALSE but not together, such as comparisons in math. Table 1.2 the operations that have a result of either TRUE or FALSE Description In Math In Computer Greater than > > Greater than or equal >= Less than < < Less than or equal <= Equal = = Not equal <> 10

11 Data : is a set of facts (ID, Name, address, telephone #,mark..), observations (cloudy weather, fast cars), remarks or comments (the mosque is crowded of students during exams, medicine students always having higher marks) and Ideas (letter, poem, essay), collected from a particular statistical society and entered to the computer for processing. Information: is a set of results that are output from the computer after processing the data. Processing: means performing computer operations like arithmetic & logical operations on an entered set of data, in order to get output information that is useful for the user. Table 1.3 gives some quantities to show the difference between Data and Information. Table 1.3 the difference between Data and Information. Data Marks Students names Dirty picture Noisy song Information Sum, Average, Sorting marks Arranging the in alphabetic order Clean picture Filtered song User : is the one who makes use of the entered data to the computer and gets information useful for human or another computer 11

12 IT (information technology) is a term that encompasses all forms of technology used to create, store, exchange, and use information in its various forms (business data, voice conversations, still images, motion pictures, multimedia presentations, and other forms, including those not yet conceived). This term is used for both telephony and computer technology. 1.3 Basic Elements of Computer System The basic elements of a computer system are Mouse, Keyboard, monitor, memory, CPU, motherboard, Hard Disk, Speakers, Modem, power supply and processor, Fig Mouse: Mouse is used for operating the system. Nowadays, optical and wireless mousses are more popular as compared to simple mouse. Keyboard: Keyboard is used to input data in to the system so that the system gives output to the user. Therefore, the keyboard is an integral part of the input system. A computer is essentially incomplete without a keyboard. Monitor: Monitor, which again is a very essential part of the computer system, displays the actions that the computer performs on our command. Motherboard: Motherboard again a necessary element of the computer system that contains different elements as memory, processor, modem, slots for graphic cards and LAN card. 12

13 Fig. 1.1 Basic Elements of a computer system Hard Disk: Hard disk is used to store data permanently on computer. Modem: Modem is used to make a connection with the Internet. Two types of modems are widely used, namely; software modems and hardware modems. 13

14 Speakers: Speakers are also included in basic elements of a computer. It is not indispensible element as a computer can perform without it. 1.4 Computer Tasks When a computer is asked to perform a job, it handles the task in a very special way. It accepts the data from the user. This is called input. It stored the data until it is ready for use. The computer has memory chips, which are designed to hold data until it is needed. Then, it processes the data. The computer has an electronic brain called the Central Processing Unit (CPU), which is responsible for processing all data and instructions given to the computer. Then it returns the processed information to the user. This is called output. As shown in Fig 1.2, there are four main building blocks in a computer's functioning input, processor, output and memory. The data is entered through input devices like the keyboard, disks or mouse. These input devices help convert data and programs into the language that the computer can process. The data received from the keyboard is processed by the CPU, i.e. the Central Processing Unit. The CPU controls and manipulates the data that produce information. The CPU is usually housed within the protective cartridge. The 14

15 Fig 1.2 Block diagram of computer processed data is either stored in the memory or sent to the output device, as per the command given by the user. The memory unit holds data and program instructions for processing data. Output devices translate the processed information from the computer into a form that we can understand Components of Computer System a) Computer Hardware: it mainly consists of: i- Input unit: Keyboard Mouse Scanner Microphone Joystick ii- Processing unit Central Processing unit (CPU) Arithmetic & Logical unit (ALU) 15

16 Control unit Registers In a computer, a register is one of a small set of data holding places that are part of a computer processor. A register may hold a computer instruction, a storage address, or any kind of data (such as a bit sequence or individual characters).. Data Registers : is the register of a computer's control unit that contains the data to be stored in the computer storage Address Registers: is a CPU register that either stores the memory address from which data will be fetched to the CPU or the address to which data will be sent and stored. Status Registers: The status register is a hardware register which contains information about the state of the processor Program Counter: A program counter is a register in a computer processor that contains the address (location) of the next instruction to be executed. General purpose Registers iii- Memory Units 16

17 Main Memory Unit Random Access Memory (RAM) This is the area of memory where data and program instructions are stored while the computer is in operation. This is temporary memory. NOTE: The data stored in RAM is lost forever when the power is turned off. For this reason it is very important that you save your work before turning off your computer. This is why we have peripheral storage devices like your computer s hard disk and floppy diskettes. It is a primary storage or random access memory (RAM). It temporarily holds data and programs for use during processing (volatile). Any information stored in RAM is lost when the computer is turned off. RAM is the memory that the computer uses to temporarily store the information as it is being processed. The more information being processed the more RAM the computer needs. RAM consists of locations or cells. Each cell has a unique address which distinguishes it from other cells. Read Only Memory (ROM) 17

18 ROM is a small area of permanent memory that provides startup instructions when the computer is turned on. You can not store any data in ROM. The instructions in ROM are set by the manufacturer and cannot be changed by the user. The last instruction in ROM directs the computer to load the operating system. Programmed at manufacturing time. Its contents cannot be changed by users. It is a permanent store. Other kinds of memory PROM: Programmable (ROM) Read Only Memory. EPROM: Erasable (PROM)Programmable Read Only Memory Cache Memory Registers: not part of the main memory. Secondary Memory Unit Your files are stored in permanent memory only when saved to your disk in a: drive or saved to your computer's hard disk, Drive c: In the Floyd College labs, you can also save your work to a network drive. We are mainly going to discuss: 18

19 Hard disk Floppy disk Tape drive CD-ROM Flash Memory iv- Output unit Monitor Speakers Printer ( Impact, Dot Matrix, Non- Impact, Ink Jet, Laser) b) Motherboard The motherboard is the main component inside the case. It is a large rectangular board with integrated circuitry that connects the various parts of the computer such as the CPU, RAM, Disk drives (CD, DVD, Hard disk or any others) as well as any other peripherals connected via the ports or the expansion slots. Components directly attached to the motherboard include: The central processing unit (CPU) performs most of the calculations that enable a computer to function and is sometimes referred to as the "brain" of the computer. It is usually cooled by a heat sink and fan. The chip set aids communication between the CPU and the other components of the system, including main memory. RAM (Random Access Memory) stores all running processes (applications) 19

20 and the current running OS. The BIOS includes boot firmware and power management. The Basic Input Output System tasks are handled by operating system drivers. Internal Buses connect the CPU to various internal components and to expansion cards for graphics and sound. c) Removable Media Devices CD (compact disc): The most common type of removable media, suitable for music and data. DVD (digital versatile disc): A popular type of removable media that has the same size as a CD but stores up to 12 times as much information. The most common way of transferring digital video and is popular for data storage. DVD-ROM Drive: A device used for reading data from a DVD DVD Writer: A device used for both reading and writing data to and from a DVD DVD-RAM Drive: A device used for rapid writing and reading of data from a special type of DVD Blu-ray Disc: A high density optical disc format for data and high-definition video that can store seventy times as much information as a CD BD-ROM Drive: A device used for reading data from a Blu-ray disc BD Writer: A device used for both reading and writing data to and from a Bluray disc 20

21 HD DVD: A discontinued competitor to the Blu-ray format Floppy disk: An outdated storage device consisting of a thin disk of a flexible magnetic storage medium used today mainly for loading RAID drivers Iomega Zip drive: An outdated medium-capacity removable disk storage system, first introduced by Iomega in 1994 USB flash drive: A flash memory data storage device integrated with a USB interface, typically small, lightweight, removable and rewritable with varying capacities from hundreds of megabytes (in the same ballpark as CDs) to hundreds of gigabytes (surpassing, at great expense, Blu-ray discs) Tape drive: A device that reads and writes data on a magnetic tape, used for long term storage and backups d) Secondary Storage This hardware keeps data inside the computer for later use and retains it even when the computer has no power. Hard disk: A device for medium-term storage of data Solid-state drive: A device quite similar to the hard disk, but containing no moving parts and which stores data in a digital format e) Sound Card This device enables the computer to output sound to audio devices, as well as 21

22 accept input from a microphone. Most modern computers have sound cards built-in to the motherboard, though it is common for a user to install a separate sound card as an upgrade. Most sound cards, either built-in or added, have surround sound capabilities. f) Other Peripherals In addition, hardware devices can include external components of a computer system. The following are either standard or very common. They include various input and output devices, usually external to the computer system. Text input devices Keyboard: A device to input text and characters by pressing buttons (referred to as keys) Pointing devices: A pointing device that detects two-dimensional motion relative to its supporting surface. It consists of an exposed protruding ball housed in a socket that detects rotation about the two axes. Optical Mouse is an example of such devices that uses light to determine motion Trackball. Touch screen is a more advanced pointing technique that senses the user pressing directly on the display Gaming devices Joystick: A control device that consists of a handheld stick that pivots around one end, to detect angles in two or three dimensions. Gamepad is an example of it. It consists of a handheld game controller that relies on the digits/fingers (especially thumbs) to provide input. Game controller is a specific type of controller specialized for certain gaming purposes. 22

23 Image, video input devices Image scanner: A device that provides input by analyzing images, printed text, handwriting or an object. Webcam is a low resolution video camera that is used to provide visual input for transferring over the Internet. Audio input devices Microphone: An acoustic sensor that provides input by converting sound to electrical signals 1.5 Uses of Computer systems Use of Computers in Education The use of computers in the education sector has increased greatly over the past few years. a- Advantages and Disadvantages of Computers in Education: 1. Computers are the best way of teaching subjects to students. These days, all schools and colleges have computer labs where they receive practical training from their teachers. 2. Computers assist teachers in teaching their students easily and quickly. 3. Students can search for the concepts or things which they wish to know, by referring to relevant websites. 4. Increasing the knowledge of these students greatly. 5. Another advantage of computers is that it enables the students to gain knowledge of various subjects and things which are out of their school syllabus to widen their learning. 23

24 6. Computers in the classroom can help teachers to save time in teaching much more than they can do without them. 7. Charts, diagrams and figures can easily be illustrated for the students while teaching practical oriented subjects such as Algebra, Geometry, Physics, Biology or Botany Uses of computer in business Computers can be used in business from the stage of manufacturing till the stage of its sale. We cannot think of a business without a computer. Any managing work depends on computer scheduling that controls communication managing data and all the information about company and competitors. Computers can keep records of all the employees Uses of Computers in Hospitals Since almost 2 decades, computers have been included in hospitals and medical clinics throughout the world. Some uses of computers in hospitals do not involve treating patients but help medical staff and doctors to handle information and data in a better manner. a- Application of Computers in Hospitals Handling Medical Data Scanning and Imaging Examination and Monitoring b- Advantages of Computers in Hospitals 24

25 Precise tests and medical examinations Faster medical alerts, which are more accurate time-wise Enhanced data about patients medical history Precision in diagnosis Precision in billing Automated updating of medical history Uses of Computers in Airports Computers are used in airports to: a) Keep track of the planes' locations, speed, direction, status, etc. b) Monitor security devices like cameras, x-ray machines, and metal detectors c) Keep up with the departure/arrival status d) Communicate over screens audio systems, and paging devices e) It is used for saving, who have booked the tickets 1.6 History of Computers& Computer Generations Using size and features as the bases, computers are classified into various generations. These generations of computers are discussed below: FIRST GENERATION: (The Vacuum Tube Era) The first generation computers were bulky in size. They were able to execute hundreds of instructions per second and were expensive as well. They used vacuum tubes as their main components. Machine language is a first generation language, for example EDVAC, UNIVAC etc. 25

26 1.6.2 SECOND GENERATION: (The Era of the Transistor) The second-generation computers were smaller in size as compared to the first generation computers. These were capable of executing thousands of instructions per second, with a transistor as its main component. Assembly language is the second generation language in which programs were written using mnemonic codes, for example, PDP (Programmed data processor), PDP1 etc THIRD GENERATION: ( Miniaturizing the Computer ) The third generation computers were more advanced and used integrated circuits. These computers contained thousands of components per circuit. They were cheaper than second-generation computers. The languages used in this generation were BASIC, COBOL etc. for example, IBM 307 Series, PDP II etc FOURTH GENERATION: over 1971 (The Microprocessor Era) The fourth generation computers used complex circuits like the large-scale integrated circuits called microprocessors or chips, which surprisingly cost less than the third generation computers. These computers were able to execute millions of instructions per second. The languages used in this generation are C++, SQL etc. for example, CRAY 2, IBM 3090/600 Series FIFTH GENERATION: Updated (super/ultra large-scale integrated circuits Era) These computers work on artificial languages (AI) like LISP, PROLOG etc. 26

27 They use super/ultra large-scale integrated circuits, which is also called parallel processing method. They execute billions of instructions per second, for example, Laptops, Palmtops, PDA (Personal Digital Assistant), Tablets, etc. Different kinds of languages emphasize different parts about the problem, and so are better at describing different aspects of the solution or even different kinds of problems and solutions. Computer Science is ever evolving, so there is continual evolution of the concepts we need to use and the notations for describing these concepts. Operational languages, for example, express how something is achieved, and makes the reader figure out what is being achieved. Declarative languages express what must be achieved and make the system work out how to achieve it. The earliest languages had few restrictions, so they were very powerful, but turned out to be very dangerous to use. After a while, people developed languages that were much safer to use, but there were complaints about their lack of power. Nowadays, we see languages that are both safe and powerful. Sometimes we have to use assembly language (Low-Level Language, LLL) because there is just no other reasonable way of telling the computer what it must do. However, most programming is done in High-Level Languages (HLLs) because of productivity. It is usually easier, or more cost-effective, to use a HLL. Some of the reasons for this are: Easy to write: Useful concepts and facilities, relevant to application Easy to read: For reuse, maintenance, enhancement etc. Portability: Other compiler/toolset suppliers, users, computers - standards 27

28 Error detection and reporting 28

29 Chapter 2 Computer System Components A computer is an automatic device that performs calculations, making decisions, and has capacity for storing and processing vast amounts of information. Computer system components can mainly be divided into two main parts, namely; hardware and software. 2.1 Hardware The term hardware refers to all of the physical devices, or components, that a computer is made of. In brief, hardware is the electronic and mechanical parts of the computer. A computer is not one single device, but a system of devices that all work together. Like the different instruments in a symphony orchestra, each device in a computer plays its own part. If you have ever shopped for a computer, you ve probably seen sales literature listing components such as microprocessors, memory, disk drives, video displays, graphics cards, and so on. Unless you already know a lot about computers, or at least have a friend that does, understanding what these different components do might be challenging. Figure 1 represents the general block diagram for the hardware parts of a digital computer. As previously mentioned, typical computer system consists of the following major components: The central processing unit (CPU) Main memory Secondary storage devices 29

30 Input devices Output devices Figure 2.1 General block diagram for the hardware parts of a digital computer The CPU When a computer is performing the tasks that a program tells it to do, we say that the computer is running or executing the program. The central processing unit, or CPU, is the part of a computer that actually runs programs. The CPU is the most important component in a computer because without it, the computer could not run software. In the earliest computers, CPUs were huge devices made of electrical and mechanical components such as vacuum tubes and switches. 2.2 How Computers Store Data CONCEPT: All data that is stored in a computer is converted to sequences of 0s and 1s. A computer s memory is divided into tiny storage locations known as bytes. One byte is only enough memory to store a letter of the alphabet or a small number. In order to do anything meaningful, a computer has to have lots of bytes. Most computers today have millions, or even billions, of bytes of memory. Each byte is divided into eight smaller storage locations known as bits. The term bit stands for binary digit. Computer scientists usually think of bits as tiny switches that can be either on or off. Bits aren t actual switches, however, at least not in the conventional sense. In most computer systems, bits are tiny 30

31 electrical components that can hold either a positive or a negative charge. Computer scientists think of a positive charge as a switch in the on position, and a negative charge as a switch in the off position. Figure 2.2 shows the way that a computer scientist might think of a byte of memory: as a collection of switches that are each flipped to either the on or off position. Figure 2.2 Think of a byte as eight switches When a piece of data is stored in a byte, the computer sets the eight bits to an on/off pattern that represents the data. For example, the pattern shown on the left in Figure 2.3 shows how the number 77 would be stored in a byte, and the pattern on the right shows how the letter A would be stored in a byte. We explain below how these patterns are determined. Figure 2.3 Bit patterns for the number 77 and the letter A 31

32 2.2.1 Storing Numbers A bit can be used in a very limited way to represent numbers. Depending on whether the bit is turned on or off, it can represent one of two different values. In computer systems, a bit that is turned off represents the number 0 and a bit that is turned on represents the number 1. This corresponds perfectly to the binary numbering system. In the binary numbering system (or binary, as it is usually called) all numeric values are written as sequences of 0s and 1s. 2.3 Software If a computer is to function, software is not optional. Everything that a computer does, from the time you turn the power switch on until you shut the system down, is under the control of software. There are two general categories of software: system software and application software. Most computer programs clearly fit into one of these two categories System Software The programs that control and manage the basic operations of a computer are generally referred to as system software. System software typically includes the following types of programs: a- Operating Systems An operating system is the most fundamental set of programs on a computer. The operating system controls the internal operations of the computer s hardware, manages all of the devices connected to the computer, allows data to be saved to and retrieved from storage devices, and allows other programs to run on 32

33 the computer. Examples of three popular operating systems: Windows 8, Windows 7, Windows Vista, Mac OS X, and Linux. b- Utility Programs A utility program performs a specialized task that enhances the computer s operation or safeguards data. Examples of utility programs are virus scanners, file compression programs, and data backup programs. c- Software Development Tools Software development tools are the programs that programmers use to create, modify, and test software. Assemblers, compilers, and interpreters are examples of programs that fall into this category Application Software Programs that make a computer useful for everyday tasks are known as application software. These are the programs that people normally spend most of their time running on their computers. Examples of two commonly used applications: Microsoft Word, a word processing program, and Adobe Photoshop, an image editing program. Some other examples of application software are spreadsheet programs, programs, web browsers, and game programs. a- General purpose Software Application software is any software used for specified applications such as: 33

34 Word Processing Spreadsheet Database Presentation Graphics Communication Tutorials Entertainment, Games b- Special purpose Software 34

35 Chapter 3 Classification of Computers Computers that process digital signals are known as Digital Computers. The Digital signal is a discrete signal with two states 0 and 1. In practice, the digital computers are used and not analog. Examples of digital computers are personal computers, supercomputers, mainframe computers etc. 3.1 Supercomputers These computers are the most powerful computers in terms of speed of execution and large storage capacity. NASA uses supercomputers to track and control space explorations. 3.2 Mainframe Computers They come as the next generation to supercomputers in terms of capacity. The mainframe computers are multi terminal computers, which can be shared simultaneously by multiple users. Unlike personal computers, mainframe computers offer time-sharing. For example, insurance companies use mainframe computers to process information about millions of its policyholders. 3.3 Minicomputers These computers are also known as midrange computers. These are desk-sized machines and are used in medium scale applications. For example, production 35

36 departments use minicomputers to monitor various manufacturing processes and assembly-line operations. 3.4 Microcomputers As compared to supercomputers, mainframes and minicomputers, microcomputers are the least powerful, but these are very widely used and rapidly gaining in popularity. 3.5 Personal Computer PC It refers to the computer that is designed for use by a single person. PCs are also called microcontrollers because these are smaller when compared to mainframes and minicomputers. The term PC is frequently used to refer to desktop computers. Although PCs are used by individuals, they can also be used in computer networks. 3.6 Desktop Computer This is the most commonly used personal computer. It comprises of a keyboard, mouse, monitor and system unit. The system unit is also known as cabinet or chassis. It is the container that houses most of the components such as motherboard, disk drives, ports, switch mode power supply and add-on cards etc. The desktop computers are available in two models- horizontal model and tower model. 36

37 3.7 Laptops Are also called notebook computers. These are the portable computers. They have a size of 8.5 x 11 inch and weigh about three-to-four kilos. 3.8 Palmtops (Tablets) They are also called handheld computers. These are computing devices, which are small enough to fit into your palm. The size of a palmtop is like an appointment book. The palmtops are generally kept for personal use such as taking notes, developing a list of friends, keeping track of dates, agendas etc. The Palmtop can also be connected to a PC for downloading data. It also provides value-added features such as voice input, Internet, cell phone, camera, movie player and GPS. 37

38 Chapter 4 Computer Networks A computer network, often simply referred to as a network, is a collection of computers and devices connected by communications channels that facilitate communication and sharing of resources among users. Networks may be classified according to a wide variety of characteristics. 4.1 Local Area Network (LAN) A Local Area Network (LAN) is a combination of programs and equipment that connect a number of personal computers. It is by far the most common type of data network. As the name suggests, a LAN serves a local area and supplies networking capability to a group of computers in close proximity to each other such as in an office building, a school or a home. Typical installations are in industrial plants, office buildings, college or university campuses or similar locations. In these locations, it is feasible for the owning organization to install high quality, high-speed communication links interconnecting nodes. Typical data transmission speeds are one to 100 megabits per second. A LAN is useful for sharing resources like files, printers, games or other applications. A LAN, in turn, often connects to other LANs and to the Internet or other WAN. Specialized operating system software may be used to configure a local area network. 38

39 Examples: The most common type of local area network is an Ethernet LAN. The smallest home LAN can have precisely two computers; a large LAN can accommodate many thousands of computers. Many LANs are divided into logical groups called subnets. An Internet Protocol (IP) "Class A" LAN can, in theory, accommodate more than 16 million devices organized into subnets. Unfortunately, the networking software and operating systems used with the PC, LANs were quite different from the networking software used on midrange and mainframe computers and office automation equipment (for example, dedicated word processing machines and intelligent copiers). This, of course, set up the predictable and inevitable conflict between PCs, office automation equipment and the larger midrange and mainframe computers. Figure 4.1 Local area network 39

40 4.1.1 LAN TOPOLOGIES Whether the purpose of the LAN is to interconnect PCs, minicomputers, or both are almost extraneous; the first issue is often selecting the topology of the LAN. Figure 4.2 illustrates the different LAN Topologies. This choice dictates the cable, cabling methodology and the networking software that can operate on the LAN. The three basic topologies are the ring, the star and the bus or tree. Figure 4.2 the different LAN Topologies 40

41 4.1.2 Linear Bus Topology A linear bus topology consists of a main run of cable with a terminator at each end, Figure 4.3. All nodes (file server, workstations, and peripherals) are connected to the linear cable. Figure 4.3 Linear Bus topology a- Advantages of a Linear Bus Topology Easy to connect a computer or peripheral to a linear bus. Requires less cable length than a star topology. b- Disadvantages of a Linear Bus Topology Entire network shuts down if there is a break in the main cable. Terminators are required at both ends of the backbone cable. Difficult to identify the problem if the entire network shuts down. Not meant to be used as a stand-alone solution in a large building. 41

42 4.1.3 Star Topology A star topology is designed with each node (file server, workstations, and peripherals) connected directly to a central network hub, switch, or concentrator, Figure 4.4. Figure 4.4 Star topology Data on a star network passes through the hub, switch, or concentrator before continuing to its destination. The hub, switch, or concentrator manages and controls all functions of the network. It also acts as a repeater for the data flow. This configuration is common with twisted pair cable; however, it can also be used with coaxial cable or fiber optic cable. 42

43 a- Advantages of a Star Topology Easy to install and wire. No disruptions to the network when connecting or removing devices. Easy to detect faults and to remove parts. b-disadvantages of a Star Topology Requires more cable length than a linear topology. If the hub, switch, or concentrator fails, nodes attached are disabled. More expensive than linear bus topologies because of the cost of the hubs, etc Tree or Expanded Star A tree topology combines characteristics of linear bus and star topologies. It consists of groups of star-configured workstations connected to a linear bus backbone cable, Figure 4.5. Tree topologies allow for the expansion of an existing network, and enable schools to configure a network to meet their needs. 43

44 Figure 4.5 Tree topology a- Advantages of a Tree Topology Point-to-point wiring for individual segments. Supported by several hardware and software venders. b-disadvantages of a Tree Topology Overall length of each segment is limited by the type of cabling used. If the backbone line breaks, the entire segment goes down. Star and ring network topologies are sometimes combined into one network to provide a higher degree of fault tolerance. Because a star network is susceptible to a failure in the hub and a ring network is sensitive to a break 44

45 in the ring, combining both forms offer an alternate route in case one topology fails. 4.2 Wide Area Network (WAN) A Wide Area Network (WAN) is a collection of LANs. A WAN spans a large geographic area, such as a state, a province or a country. WANs often connect multiple smaller networks, such as local area networks (LANs) or metro area networks (MANs), Figure 4.6. World's most popular WAN is the Internet. Some segments of the Internet, like VPN-based extranets, are also WANs in themselves. Finally, many WANs are corporate or research networks that utilize leased lines. WANs generally utilize different and a good deal of expensive networking equipment than do LANs. Key technologies often found in WANs include SONET, Frame Relay and ATM. Figure 4.6 Wide Area Network 45

46 Wide Area Network (WAN) is a computer network that covers a broad area (i.e. any network, whose communications links cross metropolitan, regional, or national boundaries). This is in contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs) or metropolitan area networks (MANs), which are usually limited to a room, building, campus or specific metropolitan area (e.g. a city) respectively WAN Connection Technology Options There are several ways to connect Nonstop S-series servers to WANs, including via the Server Net Wide Area Network (SWAN) or SWAN 2 concentrator, which provides WAN client connectivity to servers that have Ethernet ports and appropriate communications software. You can also use the Asynchronous Wide Area Network (AWAN) access server, which offers economical asynchronous-only WAN access. Several options are available for WAN connectivity: Transmission rates usually range from 1200 bps to 24 Mbps, although some connections such as ATM and Leased lines can reach speeds greater than 156 Mbps. Typical communication links used in WANs are telephone lines, microwave links and satellite channels. Recently with the proliferation of low cost of Internet connectivity, many companies and organizations have turned to VPN to interconnect their 46

47 networks, creating a WAN in that way. Companies such as Cisco, New Edge Networks and Check Point offer solutions to create VPN networks. 47

48 Chapter 5 General Computer Topics 5.1 Computer Crimes Computer crime refers to any crime that involves a computer and a network. The computer may have been used in the commission of a crime, or it may be the target. Net crime refers to criminal exploitation of the Internet. Computer crime encompasses a broad range of activities. Generally, however, it may be divided into two categories: (1) Crimes that target computers directly; (2) Crimes facilitated by computer networks or devices, the primary target of which is independent of the computer network or device. Crimes that primarily target computer networks or devices include: Computer viruses: A computer virus is a computer program that can replicate itself and spread from one computer to another. Denial-of-service attacks: In computing, a denial-of-service attack (DoS attack) or distributed denial-of-service attack (DDoS attack) is an attempt to make a machine or network resource unavailable to its intended users. 48

49 Malware (malicious code) : Malware, short for malicious software, is software used or created to disrupt computer operation, gather sensitive information, or gain access to private computer systems. It can appear in the form of code, scripts, active content, and other software Spam: Spam, or the unsolicited sending of bulk for commercial purposes, is unlawful in some jurisdictions. While anti-spam laws are relatively new, limits on unsolicited electronic communications have existed for some time. Fraud: Computer fraud is any dishonest misrepresentation of fact intended to let another to do or refrain from doing something which causes loss. In this context, the fraud will result in obtaining a benefit by: Altering computer input in an unauthorized way. This requires little technical expertise and is not an uncommon form of theft by employees altering the data before entry or entering false data, or by entering unauthorized instructions or using unauthorized processes; Altering, destroying, suppressing, or stealing output, usually to conceal unauthorized transactions: this is difficult to detect; Altering or deleting stored data; Altering or misusing existing system tools or software packages, or altering or writing code for fraudulent purposes. Other forms of fraud may be facilitated using computer systems, including bank fraud, identity theft, extortion, and theft of classified information. 49

50 5.2 Computer Viruses A computer virus is an application program designed and written to destroy other programs. It has the ability to link itself to other programs and copy itself (it looks as if it repeats itself). Monkes, ABC, Crabs and CIH are some virus examples Viruses A virus program is man-made and it infects programs, documents, databases and more. It can hide and reproduce. Besides, it can lay dormant (inactive) and then activate A variety of highly contagious viruses can spread from computer to computer, much like the way biological viruses attack and spread among human beings. Besides, it can infect programs and databases, and it can also hide and duplicates itself within legitimate programs. These program viruses can reside on and pass between magnetic disks. Most people who write and circulate virus programs fall into one of the following two groups: the first uses viruses to show off for their peers, while the other which is far more dangerous group, creates viruses with malicious intent. There are three main computer viruses. The first is Macro viruses which is written into the program macro and shuts down functions. The second is 50

51 Worm, that makes copies of itself and interfere with normal operations. The last virus is Trojan horse. The three primary sources of computer viruses are: o The Internet :Via downloads and exchanges o Secondary storage: Exchanging disks o Computer networks : Can spread from one network to another Now, the most important question is: How do you know if you have a virus? The answer comes when you notice one of the following symptoms. Lack of storage capability Decrease in the speed of executing programs Unexpected error messages Halting the system Virus Protection The software package distributed with new PCs always includes an antiviral program. The best way to cope with viruses is to recognize their existence and use an antiviral or antivirus program. Some tips that will help minimize your vulnerability to viruses: 1. Delete s from unknown or suspicious, untrustworthy (unreliable) sources, especially those with files attached to an . 51

52 2. Never open a file attached to an unless you know what it is, even if it appears to come from a friend. 3. Download files from the Internet only from legitimate and reputable sources. 4. Update your antivirus software at least every two weeks as over 200 viruses are discovered each month. 5. Backup your files periodically 6. Traditionally virus protection has been at the PC or client level. However, this may change as companies look to network and Internet service providers for more services. 5.3 Computer Ethics You shall not use a computer to harm other people. You shall not snoop around in other people's computer files. You shall not use a computer to steal. You shall not use other people's computer resources without authorization or proper compensation. You shall always use a computer in ways that show consideration and respect for your fellow humans. 52

53 Chapter 6 Introduction to Internet 6.1 Identify each of the ARPANET and the INTERNET ARPANET was the network that became the basis for the Internet. Based on a concept first published in 1967, ARPANET was developed under the direction of the U.S. Advanced Research Projects Agency (ARPA). In 1969, the idea became a modest reality with the interconnection of four university computers. The initial purpose was to communicate with and share computer resources among mainly scientific users at the connected institutions. 6.2 Basic Internet Definition ARPANet - The precursor to the Internet. ASCII - American Standard Code for Information Interchange. The de facto world wide standard code for alphanumeric characters. 53

54 Blacklist - Describes inappropriate advertisers on Usenet newsgroups and via junk . Browser - A program that is specifically used to look at various WWW resources. Client - Any computer that makes use of services available from other computers. Domain Name - A unique name that identifies an Internet site. The name always has two or more parts separated by a dot. The last part of the name identifies the site ( i.e. gov for government, edu for education, com for commercial, or net for network). An electronic street address. - Messages, usually text, sent from one person to another via a computer. Fire Wall - A combination of hardware and software that separates a LAN into two or more parts for security purposes. Host - A computer or software package which provides a specific kind of service to other computers. One that is seen by other computers on the Internet. LAN - Local Area Network. Several computers located in the same physical location which are connected together in order to share information and services. Modem - A device that allows a computer to use a phone line to communicate with another computer. Protocol - The rules of conduct which enables a computer to communicate with another computer. PPP - A protocol that allows a computer to use a telephone line and a modem to make TCP/IP connections. Server - Any computer that makes services available to other computers. TCP/IP - Transmission Control Protocol/Internet Protocol. This is the protocol which defines the Internet. URL - Uniform Resource Locator. A unique name that identifies an Internet site. WWW - World Wide Web. The universe of hypertext servers. 6.3 Introduction to Internet 54

55 The internet in simple terms is a network of the interlinked computer networking worldwide, which is accessible to the general public. These interconnected computers work by transmitting data through a special type of packet switching which is known as the IP or the internet protocol. The Internet, sometimes called simply "the Net," is a worldwide system of computer networks - a network of networks in which users at any one computer can, if they have permission, get information from any other computer (and sometimes talk directly to users at other computers). The World Wide Web (www) is only a portion of what makes up the internet, but it is the fastest growing part of the internet. The Web lets people, organizations and companies publish information for other people to see. This makes the Web a very useful tool for finding information on just about any topic. The Web is a large number of computer documents or "Web pages" that are stored on computers around the world and are connected to one another using hyperlinks. These Web pages can be seen by anyone through their computer's "Web Browser," which is the program you are using now. A group of Web pages that follow the same theme and are connected together with hyperlinks is called a "Web site." Web sites and Web pages are written in a coding language that makes it possible to add pictures, sound and interactivity to plain old text, making people's reading experience more exciting. 6.4 What are the Browsers & Search Engines Web browsers are programs used to explore the Internet. There are many Web browser programs available including Netscape Navigator, Internet Explorer and Opera. Internet Explorer is the Internet browser made by Microsoft and comes with Windows operating system. 55

56 A Web Search Engine is designed to search for information on the World Wide Web. The search results are generally presented in a line of results often referred to as search engine results pages (SERPs). The information may be a specialist in web pages, images, information and other types of files. 56

57 Google is the most popular search engine in the world, and a multinational, publicly-traded organization built around the company's hugely popular search engine. User can search for any information by writing what he is looking for in the search text box. Google can view the searched information as a web pages, pictures and there is a part for Maps, YouTube, and news. Google have its own Application called Gmail. 6.5 What is and How to Use it? , sometimes written as , is simply the shortened form of electronic mail, a system for receiving, sending, and storing electronic messages. It has gained nearly universal popularity around the world with the spread of the Internet. In many cases, has become the preferred method for both personal and business communication. A-How To Create The most popular programs in the internet world are Yahoo and Hotmail. First of all the user must create a new account in one of these programs to make an . That will be by pressing on Create New Account to fill some information like personal information and pick up an address. If no problems occurred such as missing information then the user can establish using the for sending and receiving information. 57

58 Messages sent by electronic mail normally reach a recipient s account within seconds. They frequently include more than just text; images and numerous types of formatted documents are now easily included as attached files. 58

59 Moreover, it is no longer necessary to be sitting in front of a PC to send or receive an . A variety of mobile devices, such as tablet computers and smart phones, make it possible manage correspondence on the go. If the user wants to read the coming s he must press on inbox then pressing on the message. If the user wants to write a message to someone then he must press on Compose Message. 6.6 What is Signatures & Signature Files A- Sending a Message When the user wants to send a message he must know the address for the recipient in the other side. There is a text box named be To to write the address in it. Then the user can write the title of his message in a text box named by Subject. Then he can write the message in the bigger text box and then press on Send. B-Compose Message 59

60 C-Attaching Files Also the user can attach a file which can contain a text, pictures or videos by pressing on Attachment button for attaching any file saved in the computer. 6.7 Internet Behavior and ETHICS You shall not use internet to harm other people. You shall not snoop around in other people's internet files. You shall not use a internet to steal or hack. You shall not use other people's internet resources without authorization or proper compensation. You shall always use internet in ways that show consideration and respect for your fellow humans. You should not upload articles that may scratch others psychological manners. 60

61 Chapter 7 Microsoft Windows 7 Part1: Getting Started with Windows7 Fundamentals 7.1 What is Windows 7? Windows 7 is the latest version of a series of Operating Systems before Windows 8 that Microsoft has produced for use on personal computers. Windows 7 is an operating system, which is a program that lets you run your computer A program is a set of instructions written for a computer to execute. It uses a Graphical User Interface (GUI) that allows you to visually interact with your computer s functions in a logical, fun and easy way. 61

62 7.2 Previous versions of windows Release date Product name May 1990 Windows 3.x July 1993 Windows NT August 1995 Windows 95 June 1998 Windows 98 February 2000 Windows 2000 September 2000 Windows Me October 2001 Windows XP November 2006 (volume licensing) January 2007 (retail) Windows Vista July 2007 Windows Home Server February 2008 Windows Server 2008 October 22, 2009 Windows 7 62

63 7.3 What is new in Windows 7? New Taskbar (Larger icons and hidden icons in the Taskbar) New Start Icon Desktop icons like Computer and My Documents are removed and accessed through the Start Menu Quick Launch toolbar has been replaced by pinning a program to the Taskbar Aero Snap, Shake and Peek Jump Lists for easier access A Search Bar in the Start Up Menu The "Run" command is accessed through the Start Menu's Search Bar 7.4 What are the improvements in Windows7 than Vista and XP? Faster and smoother gaming components Parental Controls for monitoring computer use Improved Start Up, Sleep and Resume performance 63

64 Improved power management saves memory and battery life Libraries to improve file access and organization Action Center for system maintenance, backups, troubleshooting and more 7.5 Advantages of Windows 7 More effective than the old versions Faster with using CPU Graphic 3D Using hardware with the most effective ability No useless index like Window Vista It s firm although it s a test version. Decreasing rate of closing screen. Remembering the last URL that you enter Virtualization and reproducing the work as well. It s able to use applications of Windows Vista and some of Windows XP. 7.6 Drawbacks of Windows 7 Requiring large space for installing Some programs on Windows XP maybe cannot work with Windows 7. 64

65 Having a few driver hardware Sometime it have bug of IE 8 beta on some web site. 7.7 Windows 7 Desktop Windows 7 desktop, which acts as your work area Icons are small images that represent items such as the Recycle Bin on your computer A file is a collection of stored information The Recycle Bin is where you place the files and folders that you don t need any more and want to delete The desktop background is the shaded area behind your desktop objects 65

66 On the desktop background, you can place icons, called shortcuts, which you can double-click to access programs, files, folders, even devices that you use frequently Gadgets are optional programs that present helpful or entertaining information on your desktop 7.8 Windows 7 Taskbar The taskbar is the thin strip that runs across the bottom of your screen. It is split into a number of different areas: a round Start button, Quick Launch icons, a notification area, and a clock. All other areas are the Taskbar itself. The image below shows where the different areas are: 66

67 The Start button is explained in a section all of its own, as it's probably the most important area of the Taskbar. There is one more area on the Taskbar, and it's easily overlooked - the Show Desktop button. In the images above, you can just see a narrow rectangle to the right of the clock: Click this button to minimize all open programmes and reveal the desktop. 7.9 Quick Launch Icons Quick launch icons, meaning you can quickly launch any of the programmes you find next to start button. When you hold your mouse over one of the icons, you'll see a small popup rectangle that shows you a preview of any open windows. In the image below, we're 67

68 holding our mouse over the Firefox icon. (Firefox is a web browser used to display internet pages. It's Internet Explorer's main competitor.) In Windows Vista, however, the icons will be smaller, and there's no popup Notification Area The Notification area, formally called the System Tray, is the area of the Taskbar where you can view programmes and tasks that are running in the background, as well as view important messages about updating your computer. (Although the clock is considered part of the Notification area, we'll look at this separately.) In the image below, the Notification area shows three icons: 68

69 The first one, the white arrow, is for hidden icons. Click the white arrow to see which icons have been hidden Probably the only one of the four icons above that you'll have is the speaker icon. This sets the volume for your speakers If yours is too low, click the speaker icon to see a slider that you can move up and down: 69

70 4. The second of the three icons in the Notification area is a white flag. This flag alerts you to issues that need to be taken care of. Click the flag icon to see if there are any problems: 5. As you can see, Windows 7 is telling us that there is 1 message, and that it's to do with Windows Defender. You can click on the "1 message" heading at the top, or on the message itself. You can also open the "Action Center" from here. 6. The third icon that appears in the Notification area (on our computer, anyway) is a Network icon. This tells us that we have an internet connection, and there are no problems. If the internet access is down, there will be a red X through this icon: 7. The red X will disappear when the problem with the internet is solved Windows Aero Windows Aero is a set of special effects for selected versions of Window 7 that gives windows transparent backgrounds and fine animations upon minimizing, maximizing, and moving When you arrange windows using Aero, the windows can appear in a 3-D stack that you can quickly view without having to use the taskbar 70

71 When you point to a taskbar button, Aero displays a small preview of the file, a feature called Aero Peek Your computer s hardware must also support Windows Aero to view and work with these features 7.12 Jump Lists A Jump List is what you'll see when you right-click on a program icon on the Windows 7 taskbar (or Start menu). What appears depends on the 71

72 specific application, but typically contains a list of frequently or lastviewed files, as well as quick access to common commands. 72

73 73

74 7.13 Using Command Buttons, Menus, and Dialog Boxes Command buttons let you issue instructions to modify program objects Some command buttons reveal menus Some menu commands automatically display a dialog box A dialog box is a type of window in which you specify how to complete an operation A dialog box may have one or more tabs for organizing related settings together on a single sheet 74

75 7.14 A Sample Dialog Box 75

76 7.15 Dialog Box Elements 76

77 Part 2: Getting Started with Windows7 Practice and Skills Gaining 77

78 Chapter 8 Microsoft Word

79 Chapter 9 Microsoft Excel

80 Chapter 10 Microsoft PowerPoint