Catholic University College of Ghana Fiapre-Sunyani - PowerPoint PPT Presentation


Title: Catholic University College of Ghana Fiapre-Sunyani


1
Catholic University College of GhanaFiapre-Sunyan
i
System Software Input Devices
  • INFORMATION TECHNOLOGY I

Audrey Asante, Faculty of ICST
2
SYSTEM SOFTWARE
  • It enables the application software to interact
    with the computer and helps the computer manage
    its internal and external resources.
  • There are four basic types of system software
  • Operating systems
  • Utility programs
  • Language translators
  • Device drivers

3
Components of System Software
  • Operating systems are programs that operate your
    microcomputer. They coordinate computer
    resources, provide an interface between users and
    the computer, and run applications.
  • Utilities, also known as service programs,
    perform specific tasks related to managing
    computer resources or files. They include
    programs to help users identify hardware
    problems, locate lost files, and back up data.
  • Device drivers are specialized programs designed
    to allow particular input or output devices to
    communicate with the rest of the computer system.
  • Language translators convert the programming
    instructions written by programmers into a
    language that computers understand and process.

4
Functions of the Operating System
  • Booting
  • Managing storage media
  • User interface
  • Managing computer resources
  • Managing files
  • Managing tasks

5
TYPES OF OS
  • Real-time Operating System It is a multitasking
    operating system that aims at executing real-time
    applications. Real-time operating systems often
    use specialized scheduling algorithms so that
    they can achieve a deterministic nature of
    behavior. The main object of real-time operating
    systems is their quick and predictable response
    to events.

6
Real Time OS
  • They either have an event-driven or a
    time-sharing design. An event-driven system
    switches between tasks based on their priorities
    while time-sharing operating systems switch tasks
    based on clock interrupts.

7
TYPES OF OS
  • Multi-user and Single-user Operating Systems The
    operating systems of this type allow a multiple
    users to access a computer system concurrently.
    Time-sharing system can be classified as
    multi-user systems as they enable a multiple user
    access to a computer through the sharing of time.
    Single-user operating systems, as opposed to a
    multi-user operating system, are usable by a
    single user at a time.

8
Multi-user and Single-user Operating Systems
  • Being able to have multiple accounts on a Windows
    operating system does not make it a multi-user
    system. Rather, only the network administrator is
    the real user. But for a Unix-like operating
    system, it is possible for two users to login at
    a time and this capability of the OS makes it a
    multi-user operating system.

9
TYPES OF OS
  • Multi-tasking and Single-tasking Operating
    Systems When a single program is allowed to run
    at a time, the system is grouped under a
    single-tasking system, while in case the
    operating system allows the execution of multiple
    tasks at one time, it is classified as a
    multi-tasking operating system. Multi-tasking can
    be of two types namely, pre-emptive or
    co-operative.

10
Multi-tasking and Single-tasking Operating Systems
  • In pre-emptive multitasking, the operating system
    slices the CPU time and dedicates one slot to
    each of the programs. Unix-like operating systems
    such as Solaris and Linux support pre-emptive
    multitasking. Cooperative multitasking is
    achieved by relying on each process to give time
    to the other processes in a defined manner. MS
    Windows prior to Windows 95 used to support
    cooperative multitasking.

11
TYPES OF OS
  • Distributed Operating System An operating system
    that manages a group of independent computers and
    makes them appear to be a single computer is
    known as a distributed operating system. The
    development of networked computers that could be
    linked and communicate with each other, gave rise
    to distributed computing.

12
Distributed Operating System
  • Distributed computations are carried out on more
    than one machine. When computers in a group work
    in cooperation, they make a distributed system.

13
TYPES OF OS
  • Embedded System The operating systems designed
    for being used in embedded computer systems are
    known as embedded operating systems. They are
    designed to operate on small machines like PDAs
    with less autonomy. They are able to operate with
    a limited number of resources. They are very
    compact and extremely efficient by design.
    Windows CE, FreeBSD and Minix 3 are some examples
    of embedded operating systems.

14
TYPES OF OS
  • The operating systems thus contribute to the
    simplification of the human interaction with the
    computer hardware. They are responsible for
    linking application programs with the hardware,
    thus achieving an easy user access to the
    computers.

15
UTILITIES
  • There are hundreds of different utility programs.
    The five most essential utilities are
  • Troubleshooting programs that recognize and
    correct problems, ideally before they become
    serious problems.
  • Antivirus programs
  • Uninstall programs
  • Back up programs
  • File compression programs

16
UTILITY SUITES
  • Like application software suites, utility suites
    combine several programs into one package.
    Example is Norton Utilities
  • Norton Utilities is a collection of 17 separate
    troubleshooting utilities. These programs can be
    used to find and fix problems, improve system
    performance, prevent problems from occurring, and
    troubleshoot a variety of other problems.
  • Norton Antivirus
  • Norton cleansweep (guards for one to safely
    remove a program and files that are no longer
    needed. They can also protect existing files from
    damaging when new programs are installed. They
    make backups as well as clean hard disk.

17
UTILITY SUITES
  • Norton crashguard (intervenes to provide options
    for recovering current work)
  • Norton web services ( notifies of available
    software updates to be automatically installed
    from the internet)

18
Input Devices
  • Keyboard
  • Mouse

19
Keyboard Layout
  • QWERTY A standard computer keyboard is called a
    QWERTY keyboard because of the layout of its
    typing area. This keyboard is named after the
    first six  leftmost letters on the top alphabetic
    line of the keyboard.  A QWERTY keyboard might
    limit your typing speed.
  • DVORAK A keyboard with an alternative layout was
    designed to improve typing speed. Called the
    Dvorak keyboard, this type of keyboard places the
    most frequently typed letters in the middle of
    the typing area.

20
Types of Keyboard
  • Wireless keyboards The most obvious difference
    between a wireless keyboard and a normal one is
    that the former uses infrared beams to transfer
    data to the computer as opposed to the latter,
    which uses a wire. As you type, a beam of data is
    sent from your keyboard to a receiver on the
    computer. The major advantage of this is that it
    eliminates one wire from the entangled web of
    wires from behind your desk. Many people also
    prefer to have a wireless mouse along with a
    wireless keyboard.
  • It may not be possible for a corded keyboard to
    be kept in a particular place that is most
    comfortable to you. This is possible with a
    cordless keyboard, provided that it is placed in
    a position where the infrared beam is easily
    reachable by the computer. This distance can be
    different for different computers, so it makes
    sense to check the specifications before buying a
    wireless keyboard. This feature can be a problem
    for the user if an object or person happens to
    block the path of the infrared beam or the angle
    of the keyboard is not right.
  • A wireless keyboard can be a valuable component
    is you are certain that the space between your
    keyboard and computer will remain free of
    physical obstructions. It will provide freedom
    and flexibility.

21
Ergonomic keyboard
  • The ergonomic keyboard has been designed to
    relieve some of the stress caused by repetitive
    typing and make for more comfortable typing.
    Prolonged usage of the keyboard can cause carpal
    tunnel syndrome or repetitive stress injury,
    which can be very painful. The specially
    designed, contoured ergonomic keyboards are
    helpful in such cases and even recommended by
    doctors.
  • There is also a view that the traditional QWERTY
    layout is more stressful on the fingers and arms.
    Hence, the unconventional Dvorak keyboard layout
    has been designed for those who subscribe to this
    theory.
  • While there are no design specifications for
    ergonomic keyboards, they generally have a
    contoured design for greater typing comfort, as
    opposed to the standard flat keyboard.

22
Illuminated keyboards
  • Much like mobile phone keyboards, these keyboards
    are backlit so that the keys are more visible
    even in poorly lit conditions.
  • Often, when working at night, you may like to
    work only with the light of the monitor to
    prevent the glare of another light. An
    illuminated keyboard would be just the thing for
    you in such a situation. It is also great for
    multimedia presentations in boardrooms with dim
    lighting.

23
Connection Types
  • Wireless keyboard
  • PS/2 keyboard
  • USB keyboard

24
Explanation of the Keys on a Windows QWERTY
Keyboard
  •  Q  W  E  R  T  Y  "The name "QWERTY" for our
    computer keyboard comes from the first six
    letters in the top alphabet row (the one just
    below the numbers). It is also referred to as the
    "Universal" keyboard. It was the work of inventor
    C. L. Sholes, who put together the prototypes of
    the first commercial typewriter in a Milwaukee
    machine shop back in the 1860's.
  • Esc Equivalent to clicking the Cancel button. In
    PowerPoint the Esc key will stop a running slide
    show. On a web page with animations, the Esc key
    will stop the animations. On a web page that is
    loading, the Esc key will stop the page from
    loading. The keyboard combination Ctrl Esc will
    open the Start Menu.
  • F1 While working in an application, depressing
    this key will bring up the applications help
    menu. If there is no open application F1 will
    open Windows Help.

25
  • F2 Choose this key to rename a selected item or
    object.
  • F3 Depressing this key will display the Find All
    Files dialog box.
  • F4 Selects the Go To A Different Folder box and
    moves down the entries in the box (if the toolbar
    is active in Windows Explorer)
  • F5 Refreshes the current window. In Internet
    Explorer, F5 will Refresh the web page.
  • F6 Moves among panes in Windows Explorer.
  • F10 Activates menu bar options. Use right and
    left arrows to select menus and down arrows to
    display pull down menus.
  • F11 In Internet Explorer this key will allow you
    to toggle between full screen viewing mode and
    normal viewing mode.

26
  • Print Screen/SysRq Usually located at the upper
    right hand corner of your keyboard next to the
    Scroll Lock and Pause/Break keys. Often
    abbreviated PrtScr, the Print Screen key is a
    useful key supported on most PCs. In DOS,
    pressing the Print Screen key causes the computer
    to send whatever images and text are currently on
    the display screen to the printer. Some graphics
    programs and Windows, use the Print Screen key to
    obtain Screen Captures.
  • Tab This key can be used to move forward through
    options in a dialog box. Ctrl Shift Tab can
    be used to move backward through the options.
    Ctrl Tab allows movement from one open window
    to the next in an application with more than one
    open window. Alt Tab displays a list of open
    application windows. Keeping Alt depressed and
    selecting Tab cycles through the list. Releasing
    selects the highlighted application window.

27
  • Caps Lock Locks the keyboard in "Capitals" mode
    (only applies to Alpha keys). The Caps Lock key
    should be used with caution. Using ALL CAPS is a
    usability no-no as many have difficulty scanning
    text that is ALL CAPS. Also, when sending email
    in all caps, this could be misconstrued as
    shouting at someone.
  • Shift The obvious use of this key is to allow
    selection of capital letters when depressing the
    alphabet characters, or selecting the characters
    above other non-alpha keys. Depressing the Shift
    key while inserting a CD-ROM will bypass auto
    play. Shift Delete to permanently delete a
    selected item, bypasses the Recycle Bin.
  • Control Key Ctrl Depressing the Ctrl key while
    clicking allows multiple selections. Holding the
    Ctrl key down and pressing other key combinations
    will initiate quite a few actions. Some of the
    more common ones are listed below.
  • Ctrl A Select All items

28
  • Ctrl B Add or remove Bold formatting
  • Ctrl C Copy, places the selected/highlighted
    copy on the clipboard.
  • Ctrl C C Opens the clipboard.
  • Ctrl F Opens the Find what dialog box. Great
    for finding references on a web page while using
    your favorite web browser.
  • Ctrl H Replace, brings up the Find and Replace
    dialog box. Great for global find and replace
    routines while working in normal and html views
    in your favorite WYSIWYG editors like FrontPage.
    You can also use this to find and replace content
    within your Word Documents, Excel Spreadsheets,
    etc...
  • Ctrl I Add or remove Italic formatting.
  • Ctrl N Window, In Internet Explorer, opens a
    New Window. In Outlook, opens a New Mail Message.
    In most publishing programs like Word, opens a
    New Document.

29
  • Ctrl O Open, brings up a browse dialog and
    allows you to select a file to open.
  • Ctrl P Print
  • Ctrl S Save
  • Ctrl U Add or remove Underline formatting.
  • Ctrl V Paste, inserts the copy on the clipboard
    into the area where your flashing cursoris
    positioned or the area you have
    selected/highlighted.
  • Ctrl W Close, will close the document currently
    open.
  • Ctrl X Cut, removes the selected/highlighted
    copy and places it on the clipboard.
  • Ctrl Y Redo last command. Many software
    programs offer multiple Redo's by pressing Ctrl
    Y Y Y...
  • Ctrl Z Undo last command. Many software
    programs offer multiple Undo's by pressing Ctrl
    Z Z Z...
  • Ctrl Esc Open the Start menu (or use the
    Windows Key if you have one).
  • Ctrl Spell checker (pre WinXP).

30
  • Ctrl While dragging a file to copy the file.
  • Ctrl Shift While dragging a file to create a
    shortcut.
  • Ctrl Tab Allows movement (toggle) from one open
    window to the next in an application with more
    than one open window.
  • Ctrl F4 Close a window in an application
    without closing the application.
  • Ctrl F5 In Internet Explorer, Ctrl F5 will
    Refresh the web page bypassing cache (all images
    and external file references will be reloaded).
  • Windows Key
  • Windows Key On either side of the spacebar,
    outside the Alt key, is a key with the Windows
    logo. Holding the Windows key down and pressing
    another key will initiate quite a few actions.

31
  • Some of the more common are listed in the table
    below
  • Displays the Start Menu.
  • D Minimizes all windows and shows the Desktop.
  • D Opens all windows and takes you right back to
    where you were.
  • E Opens a new Explorer Window. Probably one of
    the hottest Windows keyboard shortcuts. This one
    gets a lot of hoorahs!
  • F Displays the Find all files dialog box.
  • L Lock your Windows XP computer. Logoff in
    Windows Pre-XP.
  • M Minimizes all open windows.
  • Shift M Restores all previously open windows
    to how they were before you Minimized them.
  • R Displays the Run command.
  • F1 Displays the Windows Help menu.
  • Pause/Break Displays the Systems Properties
    dialog box.

32
  • Tab Cycle through the buttons on the Task Bar.
  • Alt Alt Located on either side of the space bar.
    Holding the Alt key down and pressing another key
    will initiate various actions. Some of the more
    common ones are listed below
  • Alt F4 Closes the current active window. If
    there is no active window this opens the Shut
    Down dialog box.
  • Alt underlined letter in menu To carry out the
    corresponding command on the menu.
  • Alt left/right arrows In a browser moves
    forward or back through the pages visited in a
    window.
  • Alt Space Bar Displays the current window's
    system menu. This is the same as left clicking on
    the application icon at the top left of the
    window.
  • Alt Enter Displays a selected items properties.
    This can also be done with Alt double-click.

33
  • Alt PrtScn Captures the top window of the
    active application.
  • Alt Space Bar Displays the main window's system
    menu. This is the same as clicking on the
    application icon at the left end of the title
    bar.
  • Alt Space Bar C After the system menu is
    displayed (see above), this combination will
    close a window. This works the same way as Alt
    F4 but requires less stretch.
  • Alt - (hyphen) Displays the current window's
    system menu. This is the same as left clicking on
    the application icon at the top left of the
    window.
  • Alt Tab Displays a list of open application
    windows. Keeping Alt depressed and selecting Tab
    cycles through the list. Releasing selects the
    highlighted application window.
  • Alt  Ctrl The Application key has an image of a
    mouse pointer on a menu (between the Alt and Ctrl
    keys () to the right of your Space Bar).
    Depressing this key will display the selected
    item's shortcut window. This is the menu that is
    displayed by right-clicking.

34
  • Space Bar Insert a space between words. It is
    suggested that you utilize Tabs (or other
    formatting commands) to put distance between
    elements. Using the space bar to insert visual
    space works but would not be considered a best
    practice in page design. Double spaces between
    sentences are no longer required. This is a
    carryover from the days of fixed width fonts on a
    typewriter such as Courier, Orator, Prestige
    Elite, etc. Pressing the Space Bar while viewing
    a web page in Internet Explorer will scroll the
    page downwards. Shift Space Bar will scroll the
    page upwards.
  • Enter Creates a new Paragraph ltpgt () or what is
    referred to as a Hard Return. In any dialog box a
    selected button or command can be selected by
    depressing this key. Selected buttons can be
    recognized by their darker (dotted) borders, or
    what is referred to as Focus.
  • Shift Enter Creates a new Line Break ltbrgt () or
    what is referred to as a Soft Return.

35
  • Shift Arrow Shift Arrow Up, Down, Left or
    Right. Position your cursorat the beginning of
    the area you wish to highlight for copying. Now
    use the up, down, left or right arrow keys to
    select areas of content to be highlighted,
    copied, pasted, etc.
  • Backspace While working with text, use this key
    to delete characters to the left of the insertion
    point.
  • Home Depress and hold the Ctrl key as you select
    Home to go to the first line of a document.
  • Page Up In a browser window use the Page Up key
    to move up one full screen on a web page.
  • Delete While working with text, use this key to
    delete characters to the right of the insertion
    point. This key can also be used to delete
    selected files. If you use the keyboard
    combination Shift Delete the item is
    permanently deleted, bypassing the Recycle Bin.

36
  • End Depress and hold the Ctrl key as you select
    End to go to the last line of a document.
  • Page Down In a browser window use the Page Down
    key to move down one full screen on a web page
  • Up Arrow Navigate in a document to the line
    above. Hold the Ctrl key down as you press this
    key to move to the beginning of the second line
    above.
  • Right Arrow Navigate in a document one character
    to the right. Hold the Ctrl key down as you press
    this key to move one word to the right.
  • Down Arrow Navigate in a document to the line
    below. Hold the Ctrl key down as you press this
    key to move to the beginning of the second line
    below.
  • Left Arrow Navigate in a document one character
    to the left. Hold the Ctrl key down as you press
    this key to move one word to the left.

37
  • Keypad Keys
  • Num Lock If you want to use the numeric keypad on
    the right end of the keyboard to display numbers,
    the Num Lock key must be selected (usually a
    light above the Num Lock will indicate that it is
    on). If you want to use the keypad to navigate
    within a document, turn off Num Lock by pressing
    the key (the light will go off).
  •    (Asterisk) In Windows Explorer this expands
    everything under the current selection. Caution
    do not try this with the C Drive icon selected.
  •  -  (Minus Sign) In Windows Explorer this
    collapses the current selection.
  •    (Plus Sign) In Windows Explorer this expands
    the current selection.

38
FEATURES OF THE KEYBOARD
  • Special purpose keys are used to enter, delete,
    and edit data and to execute commands.
  • Function keys are used to execute commands
    specific to the software being used
  • Macros are also called keyboard shortcuts. It is
    a single keystroke or command used to
    automatically issue a longer, predetermined
    series of keystrokes or commands.

39
Mouse
  • The mouse is a pointing device
  • It allows for fine control of a Graphical User
    Interface.
  • The mouse parts
  • Left mouse button
  • Right button
  • Scroll wheel-for scrolling. This is an additional
    feature that has been added.

40
Mouse
  • Types of mouse
  • Mechanical Mouse device This is a type of
    computer mouse that has a rubber or metal ball on
    its underside and it can roll in every
    direction.  There are sensors within the mouse,
    which are mechanical, detect the direction in
    which the ball is moving and moves the pointer on
    the screen in the same direction.  A mouse pad
    should be used under the mouse to run on.
  • Optomechanical mouse devices This is the same
    as the mechanical mouse except that it uses
    optical sensors to the motion of the ball.  Your
    should use a mouse pad under the mouse to run on.
  • Optical mouse device This type uses a laser for
    detecting the mouse's movement.  You don't need a
    mouse pad but you can use one made for optical
    mice.  Optical mice do not have any mechanical
    moving parts.  The optical mouse responds more
    quickly and precisely than the mechanical and
    optomechanical mice and now that they have been
    around awhile the price is pretty comparable.

41
Here is how a computer mouse hooks up to the
computer
  • Serial mouse  these ones connect directly to an
    RS-232C serial port or a PS/2port.  This is the
    simplest type of connection. it requires a free
    serial port on your PC.
  • PS/2 mouse  connects to a PS/2 port.USB Mouse -
    This type of mouse has a USB connector and
    requires a free USB port.
  • Cordless mouse  These are not physically
    connected to the computer.  They rely on infrared
    or radio waves to communicate with the computer. 
    Cordless are more expensive than both the serial
    and bus mouse.  The nice thing is that there is
    no cord to constrain or get in your way. this
    type of mouse utilises batteries for its power
    supply. Optical Mouse - An optical mouse
    utilises optical electronics to track the mouse's
    position and movement, they are preferred over
    standard mechanical mice as they tend to be more
    reliable and require less maintenance.

42
Mouse
  • Applications or directions of the mouse
  • Single click
  • Double click
  • Triple click
  • Drag and drop
  • Roll over
  • Selecting
  • Pointing
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Title: Catholic University College of Ghana Fiapre-Sunyani


1
Catholic University College of GhanaFiapre-Sunyan
i
System Software Input Devices
  • INFORMATION TECHNOLOGY I

Audrey Asante, Faculty of ICST
2
SYSTEM SOFTWARE
  • It enables the application software to interact
    with the computer and helps the computer manage
    its internal and external resources.
  • There are four basic types of system software
  • Operating systems
  • Utility programs
  • Language translators
  • Device drivers

3
Components of System Software
  • Operating systems are programs that operate your
    microcomputer. They coordinate computer
    resources, provide an interface between users and
    the computer, and run applications.
  • Utilities, also known as service programs,
    perform specific tasks related to managing
    computer resources or files. They include
    programs to help users identify hardware
    problems, locate lost files, and back up data.
  • Device drivers are specialized programs designed
    to allow particular input or output devices to
    communicate with the rest of the computer system.
  • Language translators convert the programming
    instructions written by programmers into a
    language that computers understand and process.

4
Functions of the Operating System
  • Booting
  • Managing storage media
  • User interface
  • Managing computer resources
  • Managing files
  • Managing tasks

5
TYPES OF OS
  • Real-time Operating System It is a multitasking
    operating system that aims at executing real-time
    applications. Real-time operating systems often
    use specialized scheduling algorithms so that
    they can achieve a deterministic nature of
    behavior. The main object of real-time operating
    systems is their quick and predictable response
    to events.

6
Real Time OS
  • They either have an event-driven or a
    time-sharing design. An event-driven system
    switches between tasks based on their priorities
    while time-sharing operating systems switch tasks
    based on clock interrupts.

7
TYPES OF OS
  • Multi-user and Single-user Operating Systems The
    operating systems of this type allow a multiple
    users to access a computer system concurrently.
    Time-sharing system can be classified as
    multi-user systems as they enable a multiple user
    access to a computer through the sharing of time.
    Single-user operating systems, as opposed to a
    multi-user operating system, are usable by a
    single user at a time.

8
Multi-user and Single-user Operating Systems
  • Being able to have multiple accounts on a Windows
    operating system does not make it a multi-user
    system. Rather, only the network administrator is
    the real user. But for a Unix-like operating
    system, it is possible for two users to login at
    a time and this capability of the OS makes it a
    multi-user operating system.

9
TYPES OF OS
  • Multi-tasking and Single-tasking Operating
    Systems When a single program is allowed to run
    at a time, the system is grouped under a
    single-tasking system, while in case the
    operating system allows the execution of multiple
    tasks at one time, it is classified as a
    multi-tasking operating system. Multi-tasking can
    be of two types namely, pre-emptive or
    co-operative.

10
Multi-tasking and Single-tasking Operating Systems
  • In pre-emptive multitasking, the operating system
    slices the CPU time and dedicates one slot to
    each of the programs. Unix-like operating systems
    such as Solaris and Linux support pre-emptive
    multitasking. Cooperative multitasking is
    achieved by relying on each process to give time
    to the other processes in a defined manner. MS
    Windows prior to Windows 95 used to support
    cooperative multitasking.

11
TYPES OF OS
  • Distributed Operating System An operating system
    that manages a group of independent computers and
    makes them appear to be a single computer is
    known as a distributed operating system. The
    development of networked computers that could be
    linked and communicate with each other, gave rise
    to distributed computing.

12
Distributed Operating System
  • Distributed computations are carried out on more
    than one machine. When computers in a group work
    in cooperation, they make a distributed system.

13
TYPES OF OS
  • Embedded System The operating systems designed
    for being used in embedded computer systems are
    known as embedded operating systems. They are
    designed to operate on small machines like PDAs
    with less autonomy. They are able to operate with
    a limited number of resources. They are very
    compact and extremely efficient by design.
    Windows CE, FreeBSD and Minix 3 are some examples
    of embedded operating systems.

14
TYPES OF OS
  • The operating systems thus contribute to the
    simplification of the human interaction with the
    computer hardware. They are responsible for
    linking application programs with the hardware,
    thus achieving an easy user access to the
    computers.

15
UTILITIES
  • There are hundreds of different utility programs.
    The five most essential utilities are
  • Troubleshooting programs that recognize and
    correct problems, ideally before they become
    serious problems.
  • Antivirus programs
  • Uninstall programs
  • Back up programs
  • File compression programs

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UTILITY SUITES
  • Like application software suites, utility suites
    combine several programs into one package.
    Example is Norton Utilities
  • Norton Utilities is a collection of 17 separate
    troubleshooting utilities. These programs can be
    used to find and fix problems, improve system
    performance, prevent problems from occurring, and
    troubleshoot a variety of other problems.
  • Norton Antivirus
  • Norton cleansweep (guards for one to safely
    remove a program and files that are no longer
    needed. They can also protect existing files from
    damaging when new programs are installed. They
    make backups as well as clean hard disk.

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UTILITY SUITES
  • Norton crashguard (intervenes to provide options
    for recovering current work)
  • Norton web services ( notifies of available
    software updates to be automatically installed
    from the internet)

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Input Devices
  • Keyboard
  • Mouse

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Keyboard Layout
  • QWERTY A standard computer keyboard is called a
    QWERTY keyboard because of the layout of its
    typing area. This keyboard is named after the
    first six  leftmost letters on the top alphabetic
    line of the keyboard.  A QWERTY keyboard might
    limit your typing speed.
  • DVORAK A keyboard with an alternative layout was
    designed to improve typing speed. Called the
    Dvorak keyboard, this type of keyboard places the
    most frequently typed letters in the middle of
    the typing area.

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Types of Keyboard
  • Wireless keyboards The most obvious difference
    between a wireless keyboard and a normal one is
    that the former uses infrared beams to transfer
    data to the computer as opposed to the latter,
    which uses a wire. As you type, a beam of data is
    sent from your keyboard to a receiver on the
    computer. The major advantage of this is that it
    eliminates one wire from the entangled web of
    wires from behind your desk. Many people also
    prefer to have a wireless mouse along with a
    wireless keyboard.
  • It may not be possible for a corded keyboard to
    be kept in a particular place that is most
    comfortable to you. This is possible with a
    cordless keyboard, provided that it is placed in
    a position where the infrared beam is easily
    reachable by the computer. This distance can be
    different for different computers, so it makes
    sense to check the specifications before buying a
    wireless keyboard. This feature can be a problem
    for the user if an object or person happens to
    block the path of the infrared beam or the angle
    of the keyboard is not right.
  • A wireless keyboard can be a valuable component
    is you are certain that the space between your
    keyboard and computer will remain free of
    physical obstructions. It will provide freedom
    and flexibility.

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Ergonomic keyboard
  • The ergonomic keyboard has been designed to
    relieve some of the stress caused by repetitive
    typing and make for more comfortable typing.
    Prolonged usage of the keyboard can cause carpal
    tunnel syndrome or repetitive stress injury,
    which can be very painful. The specially
    designed, contoured ergonomic keyboards are
    helpful in such cases and even recommended by
    doctors.
  • There is also a view that the traditional QWERTY
    layout is more stressful on the fingers and arms.
    Hence, the unconventional Dvorak keyboard layout
    has been designed for those who subscribe to this
    theory.
  • While there are no design specifications for
    ergonomic keyboards, they generally have a
    contoured design for greater typing comfort, as
    opposed to the standard flat keyboard.

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Illuminated keyboards
  • Much like mobile phone keyboards, these keyboards
    are backlit so that the keys are more visible
    even in poorly lit conditions.
  • Often, when working at night, you may like to
    work only with the light of the monitor to
    prevent the glare of another light. An
    illuminated keyboard would be just the thing for
    you in such a situation. It is also great for
    multimedia presentations in boardrooms with dim
    lighting.

23
Connection Types
  • Wireless keyboard
  • PS/2 keyboard
  • USB keyboard

24
Explanation of the Keys on a Windows QWERTY
Keyboard
  •  Q  W  E  R  T  Y  "The name "QWERTY" for our
    computer keyboard comes from the first six
    letters in the top alphabet row (the one just
    below the numbers). It is also referred to as the
    "Universal" keyboard. It was the work of inventor
    C. L. Sholes, who put together the prototypes of
    the first commercial typewriter in a Milwaukee
    machine shop back in the 1860's.
  • Esc Equivalent to clicking the Cancel button. In
    PowerPoint the Esc key will stop a running slide
    show. On a web page with animations, the Esc key
    will stop the animations. On a web page that is
    loading, the Esc key will stop the page from
    loading. The keyboard combination Ctrl Esc will
    open the Start Menu.
  • F1 While working in an application, depressing
    this key will bring up the applications help
    menu. If there is no open application F1 will
    open Windows Help.

25
  • F2 Choose this key to rename a selected item or
    object.
  • F3 Depressing this key will display the Find All
    Files dialog box.
  • F4 Selects the Go To A Different Folder box and
    moves down the entries in the box (if the toolbar
    is active in Windows Explorer)
  • F5 Refreshes the current window. In Internet
    Explorer, F5 will Refresh the web page.
  • F6 Moves among panes in Windows Explorer.
  • F10 Activates menu bar options. Use right and
    left arrows to select menus and down arrows to
    display pull down menus.
  • F11 In Internet Explorer this key will allow you
    to toggle between full screen viewing mode and
    normal viewing mode.

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  • Print Screen/SysRq Usually located at the upper
    right hand corner of your keyboard next to the
    Scroll Lock and Pause/Break keys. Often
    abbreviated PrtScr, the Print Screen key is a
    useful key supported on most PCs. In DOS,
    pressing the Print Screen key causes the computer
    to send whatever images and text are currently on
    the display screen to the printer. Some graphics
    programs and Windows, use the Print Screen key to
    obtain Screen Captures.
  • Tab This key can be used to move forward through
    options in a dialog box. Ctrl Shift Tab can
    be used to move backward through the options.
    Ctrl Tab allows movement from one open window
    to the next in an application with more than one
    open window. Alt Tab displays a list of open
    application windows. Keeping Alt depressed and
    selecting Tab cycles through the list. Releasing
    selects the highlighted application window.

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  • Caps Lock Locks the keyboard in "Capitals" mode
    (only applies to Alpha keys). The Caps Lock key
    should be used with caution. Using ALL CAPS is a
    usability no-no as many have difficulty scanning
    text that is ALL CAPS. Also, when sending email
    in all caps, this could be misconstrued as
    shouting at someone.
  • Shift The obvious use of this key is to allow
    selection of capital letters when depressing the
    alphabet characters, or selecting the characters
    above other non-alpha keys. Depressing the Shift
    key while inserting a CD-ROM will bypass auto
    play. Shift Delete to permanently delete a
    selected item, bypasses the Recycle Bin.
  • Control Key Ctrl Depressing the Ctrl key while
    clicking allows multiple selections. Holding the
    Ctrl key down and pressing other key combinations
    will initiate quite a few actions. Some of the
    more common ones are listed below.
  • Ctrl A Select All items

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  • Ctrl B Add or remove Bold formatting
  • Ctrl C Copy, places the selected/highlighted
    copy on the clipboard.
  • Ctrl C C Opens the clipboard.
  • Ctrl F Opens the Find what dialog box. Great
    for finding references on a web page while using
    your favorite web browser.
  • Ctrl H Replace, brings up the Find and Replace
    dialog box. Great for global find and replace
    routines while working in normal and html views
    in your favorite WYSIWYG editors like FrontPage.
    You can also use this to find and replace content
    within your Word Documents, Excel Spreadsheets,
    etc...
  • Ctrl I Add or remove Italic formatting.
  • Ctrl N Window, In Internet Explorer, opens a
    New Window. In Outlook, opens a New Mail Message.
    In most publishing programs like Word, opens a
    New Document.

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  • Ctrl O Open, brings up a browse dialog and
    allows you to select a file to open.
  • Ctrl P Print
  • Ctrl S Save
  • Ctrl U Add or remove Underline formatting.
  • Ctrl V Paste, inserts the copy on the clipboard
    into the area where your flashing cursoris
    positioned or the area you have
    selected/highlighted.
  • Ctrl W Close, will close the document currently
    open.
  • Ctrl X Cut, removes the selected/highlighted
    copy and places it on the clipboard.
  • Ctrl Y Redo last command. Many software
    programs offer multiple Redo's by pressing Ctrl
    Y Y Y...
  • Ctrl Z Undo last command. Many software
    programs offer multiple Undo's by pressing Ctrl
    Z Z Z...
  • Ctrl Esc Open the Start menu (or use the
    Windows Key if you have one).
  • Ctrl Spell checker (pre WinXP).

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  • Ctrl While dragging a file to copy the file.
  • Ctrl Shift While dragging a file to create a
    shortcut.
  • Ctrl Tab Allows movement (toggle) from one open
    window to the next in an application with more
    than one open window.
  • Ctrl F4 Close a window in an application
    without closing the application.
  • Ctrl F5 In Internet Explorer, Ctrl F5 will
    Refresh the web page bypassing cache (all images
    and external file references will be reloaded).
  • Windows Key
  • Windows Key On either side of the spacebar,
    outside the Alt key, is a key with the Windows
    logo. Holding the Windows key down and pressing
    another key will initiate quite a few actions.

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  • Some of the more common are listed in the table
    below
  • Displays the Start Menu.
  • D Minimizes all windows and shows the Desktop.
  • D Opens all windows and takes you right back to
    where you were.
  • E Opens a new Explorer Window. Probably one of
    the hottest Windows keyboard shortcuts. This one
    gets a lot of hoorahs!
  • F Displays the Find all files dialog box.
  • L Lock your Windows XP computer. Logoff in
    Windows Pre-XP.
  • M Minimizes all open windows.
  • Shift M Restores all previously open windows
    to how they were before you Minimized them.
  • R Displays the Run command.
  • F1 Displays the Windows Help menu.
  • Pause/Break Displays the Systems Properties
    dialog box.

32
  • Tab Cycle through the buttons on the Task Bar.
  • Alt Alt Located on either side of the space bar.
    Holding the Alt key down and pressing another key
    will initiate various actions. Some of the more
    common ones are listed below
  • Alt F4 Closes the current active window. If
    there is no active window this opens the Shut
    Down dialog box.
  • Alt underlined letter in menu To carry out the
    corresponding command on the menu.
  • Alt left/right arrows In a browser moves
    forward or back through the pages visited in a
    window.
  • Alt Space Bar Displays the current window's
    system menu. This is the same as left clicking on
    the application icon at the top left of the
    window.
  • Alt Enter Displays a selected items properties.
    This can also be done with Alt double-click.

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  • Alt PrtScn Captures the top window of the
    active application.
  • Alt Space Bar Displays the main window's system
    menu. This is the same as clicking on the
    application icon at the left end of the title
    bar.
  • Alt Space Bar C After the system menu is
    displayed (see above), this combination will
    close a window. This works the same way as Alt
    F4 but requires less stretch.
  • Alt - (hyphen) Displays the current window's
    system menu. This is the same as left clicking on
    the application icon at the top left of the
    window.
  • Alt Tab Displays a list of open application
    windows. Keeping Alt depressed and selecting Tab
    cycles through the list. Releasing selects the
    highlighted application window.
  • Alt  Ctrl The Application key has an image of a
    mouse pointer on a menu (between the Alt and Ctrl
    keys () to the right of your Space Bar).
    Depressing this key will display the selected
    item's shortcut window. This is the menu that is
    displayed by right-clicking.

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  • Space Bar Insert a space between words. It is
    suggested that you utilize Tabs (or other
    formatting commands) to put distance between
    elements. Using the space bar to insert visual
    space works but would not be considered a best
    practice in page design. Double spaces between
    sentences are no longer required. This is a
    carryover from the days of fixed width fonts on a
    typewriter such as Courier, Orator, Prestige
    Elite, etc. Pressing the Space Bar while viewing
    a web page in Internet Explorer will scroll the
    page downwards. Shift Space Bar will scroll the
    page upwards.
  • Enter Creates a new Paragraph ltpgt () or what is
    referred to as a Hard Return. In any dialog box a
    selected button or command can be selected by
    depressing this key. Selected buttons can be
    recognized by their darker (dotted) borders, or
    what is referred to as Focus.
  • Shift Enter Creates a new Line Break ltbrgt () or
    what is referred to as a Soft Return.

35
  • Shift Arrow Shift Arrow Up, Down, Left or
    Right. Position your cursorat the beginning of
    the area you wish to highlight for copying. Now
    use the up, down, left or right arrow keys to
    select areas of content to be highlighted,
    copied, pasted, etc.
  • Backspace While working with text, use this key
    to delete characters to the left of the insertion
    point.
  • Home Depress and hold the Ctrl key as you select
    Home to go to the first line of a document.
  • Page Up In a browser window use the Page Up key
    to move up one full screen on a web page.
  • Delete While working with text, use this key to
    delete characters to the right of the insertion
    point. This key can also be used to delete
    selected files. If you use the keyboard
    combination Shift Delete the item is
    permanently deleted, bypassing the Recycle Bin.

36
  • End Depress and hold the Ctrl key as you select
    End to go to the last line of a document.
  • Page Down In a browser window use the Page Down
    key to move down one full screen on a web page
  • Up Arrow Navigate in a document to the line
    above. Hold the Ctrl key down as you press this
    key to move to the beginning of the second line
    above.
  • Right Arrow Navigate in a document one character
    to the right. Hold the Ctrl key down as you press
    this key to move one word to the right.
  • Down Arrow Navigate in a document to the line
    below. Hold the Ctrl key down as you press this
    key to move to the beginning of the second line
    below.
  • Left Arrow Navigate in a document one character
    to the left. Hold the Ctrl key down as you press
    this key to move one word to the left.

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  • Keypad Keys
  • Num Lock If you want to use the numeric keypad on
    the right end of the keyboard to display numbers,
    the Num Lock key must be selected (usually a
    light above the Num Lock will indicate that it is
    on). If you want to use the keypad to navigate
    within a document, turn off Num Lock by pressing
    the key (the light will go off).
  •    (Asterisk) In Windows Explorer this expands
    everything under the current selection. Caution
    do not try this with the C Drive icon selected.
  •  -  (Minus Sign) In Windows Explorer this
    collapses the current selection.
  •    (Plus Sign) In Windows Explorer this expands
    the current selection.

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FEATURES OF THE KEYBOARD
  • Special purpose keys are used to enter, delete,
    and edit data and to execute commands.
  • Function keys are used to execute commands
    specific to the software being used
  • Macros are also called keyboard shortcuts. It is
    a single keystroke or command used to
    automatically issue a longer, predetermined
    series of keystrokes or commands.

39
Mouse
  • The mouse is a pointing device
  • It allows for fine control of a Graphical User
    Interface.
  • The mouse parts
  • Left mouse button
  • Right button
  • Scroll wheel-for scrolling. This is an additional
    feature that has been added.

40
Mouse
  • Types of mouse
  • Mechanical Mouse device This is a type of
    computer mouse that has a rubber or metal ball on
    its underside and it can roll in every
    direction.  There are sensors within the mouse,
    which are mechanical, detect the direction in
    which the ball is moving and moves the pointer on
    the screen in the same direction.  A mouse pad
    should be used under the mouse to run on.
  • Optomechanical mouse devices This is the same
    as the mechanical mouse except that it uses
    optical sensors to the motion of the ball.  Your
    should use a mouse pad under the mouse to run on.
  • Optical mouse device This type uses a laser for
    detecting the mouse's movement.  You don't need a
    mouse pad but you can use one made for optical
    mice.  Optical mice do not have any mechanical
    moving parts.  The optical mouse responds more
    quickly and precisely than the mechanical and
    optomechanical mice and now that they have been
    around awhile the price is pretty comparable.

41
Here is how a computer mouse hooks up to the
computer
  • Serial mouse  these ones connect directly to an
    RS-232C serial port or a PS/2port.  This is the
    simplest type of connection. it requires a free
    serial port on your PC.
  • PS/2 mouse  connects to a PS/2 port.USB Mouse -
    This type of mouse has a USB connector and
    requires a free USB port.
  • Cordless mouse  These are not physically
    connected to the computer.  They rely on infrared
    or radio waves to communicate with the computer. 
    Cordless are more expensive than both the serial
    and bus mouse.  The nice thing is that there is
    no cord to constrain or get in your way. this
    type of mouse utilises batteries for its power
    supply. Optical Mouse - An optical mouse
    utilises optical electronics to track the mouse's
    position and movement, they are preferred over
    standard mechanical mice as they tend to be more
    reliable and require less maintenance.

42
Mouse
  • Applications or directions of the mouse
  • Single click
  • Double click
  • Triple click
  • Drag and drop
  • Roll over
  • Selecting
  • Pointing
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