SummarySummary Notes TERM THREE BASIC SEVEN (7) ACADEMIC YEAR 2014 ACADEMIC YEAR 2014
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- SummarySummary Notes TERM THREE BASIC SEVEN (7) ACADEMIC YEAR
2014 ACADEMIC YEAR 2014
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- BASIC TYPING SKILLS DEVEKOPMENT MANIPULATIVE KEYS ON THE
KEYBORD The computer keyboard has been divided into four main
sections for ease of use. They are; Alphanumeric keys Functional
keys Navigation/special keys Numeric keys
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- MANIPULATIVES KEY Manipulative keys are non-printing characters
that are used to change the appearance and layout of text on any
page. Examples; a. the Shift Key b. the Caps Lock Key c. the Enter
Key d. the Backspace Key e. the Tab Key f. the Delete g. the Insert
key
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- FUNCTIONS OF THE KEYS
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- THE SHIFT KEY is used in combination with other keys to produce
uppercase letters during typing. THE CAPS LOCK KEY produces
uppercase letters when pressed. THE ENTER KEY is used to move the
insertion point to next line when typing and also executes a
command in an operation. THE BACKSPACE KEY is used to delete
characters to the left of the insertion point. THE DELETE KEY is
used to delete characters to the right of the cursor.
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- COMMON KEYBOARD SYMBOLS It is impossible to write meaningful
passages without punctuation. The keyboard offers several symbols
and punctuations to help you produce meaningful and excellent
documents. Punctuation marks are symbols used to organise writing
and edit document. They are the standard non alphabetical symbols
or marks that are used to organise writing into clauses, phrases,
and sentences, and in this way make its meaning clear. Keys on the
keyboard with these marks are called punctuation keys.
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- The following are some of the punctuation marks we will be
considering; Comma (,) Full stop (.) Slash (/) Semi-colon (;)
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- Functions of the punctuation marks. Comma: A punctuation mark
(,) that represents a slight pause in a sentence or is used to
separate words and figures in a list. Slash: A slash (/) is a
punctuation mark that is used to separate optional items in a list
or to express fraction or division, it also has various uses in
computer programming. The slash is also known as virgule or forward
slash. Full stop: Complete stop or a complete halt or an end
(.)
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- A semi colon (;) is used to separate two parts of a sentence
that have a relationship to each other in terms of meaning when
each part could stand alone as a sentence in its own right.
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- Keyboard Symbols Symbol keys not requiring shift `Left single
quote -Dash =Equal sign [Left (opening) square bracket ]Right
(closing) square bracket \Backslash ;Semi-colon
Apostrophe,Comma.Period /Slash or Diagonal
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- Symbol keys requiring shift ~Tilde !Exclamation point @At
symbol #Number or Pound sign(hash) $Dollar sign %Percent sign
^Caret symbol &Ampersand *Asterisk (Left (opening) parenthesis
)Right (closing) parenthesis _Underscore +Plus sign
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- {Left (opening) bracket }Right (closing) bracket |Pipe symbol
:Colon Quotation marks Greater than symbol ?Question mark
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- GRAPHICAL USER INTERFACE (GUI) DESKTOP Definition: The desktop
screen or the graphical user interface is the colourful workspace
that appears after the computer has gone through its booting
process.
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- FEATURES OF THE WINDOWS DESKTOP The graphical user interface
differs from one operating system to another. Below are some
examples of the computer desktop.
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- START BUTTON TASK BAR NOTIFICATION AREA ICONS Windows XP
desktop Windows 7desktop
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- Windows 8 desktop and start screen
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- Icons : Icons are graphical representation of programs, files,
folders and drives on the computer desktop. Wallpaper : The
wallpaper is the background pattern for a computer screen. Every
window comes with pictures that can be used as wallpaper. Moreover,
the user can also select his / her own picture to use as a
wallpaper provided that one is saved in the computer.
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- FEATURES OF THE DESKTOP Computer icon lets the user browse the
files stored on the PC. Double-clicking on this icon shows the hard
disk, the floppy disk, the CD-ROM drive and the possible drives
installed in the computer system. It is the shortcut to a
ready-made folder on your computers hard disk. My Documents icon
contains all the documents saved on the computer without specifying
its location. COMPUTER / MY COMPUTER ICON MY DOCUMENT ICON
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- RECYCLE BIN THE INTERNET EXPLORER It is an electronic container
that keeps temporary deleted files and folders. Moreover, the
deleted files or documents can be restored back if wanted. Note
that when the user empties the recycle bin, anything that its holds
will be deleted permanently. The internet connection wizard is a
special program called a browser which interpret content of a web
page and helps the user to navigate web pages on the internet.
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- A Folder Network icon A folder is an electronic storage area
use to organize files, programs and other folders. The network icon
helps the user to connect to other computers on the network. It is
a utility for browsing network resources like the shared files, web
links and networked local printers.
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- Taskbar The taskbar is the horizontal bar usually located at
the bottom of the desktop window. The taskbar has four main
sections. The Start button which is used to launch programs. The
Quick Launch toolbar is used to quickly load programs. - The middle
section which shows tabs of all programs and files opened and
allows to switch between them. - The notification area which
includes a clock and icons that show the status of certain programs
and computer system.
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- USING START MENU USING ICONS ON THE DESKTOP
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- The Start menu gives the user access to navigate through the
system. The left pane of the start menu shows a list of programs we
use frequently while the right pane displays system options,
folders, shortcuts, the name and the picture that represents the
current user. THE START MENU
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- FIGURE OF THEE START MENU Picture of the user Name of the user
Accessories folder Items under Accessories
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- STEP 1 LAUNCHING AN APPLICATION USING THE START MENU The
technical term for opening an application is launch or load.
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- To launch an application using the Start menu, observe the
following steps: 1.Click on the Start button located on the taskbar
to display its menu. (Figure below) Start menu Start button
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- Click on a desired program name in left pane. If in any way,
the desired program could not appear, click on All Programs and
scroll through the list. Moreover, the user can also type the name
of the program in the search box and press on the Enter key to
display the search results. NB: The folders shown in All Programs
list contain other programs. For example the WordPad, Paint,
Calculator and Note Pad are under Accessories
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- STEP 2. LAUNCHING ANA PPLICATION USING DESKTOP ICONS Desktop
icons provide a shortcut to launch programs and open folders. To
launch any program using the desktop icons, use the following
methods: 1.Method 1: Double-click the program shortcut icon on the
Windows Desktop to launch it.
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- 2. Method 2: Click the program icon on the Windows desktop and
press Enter key on the keyboard. 3. Method 3: Right click the
program icon on the desktop. In the drop-down menu or list of
items, click on Open to launch the program.
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- CREATING A SHORTCUT OF A PROGRAM ON THE DESKTOP. To create a
shortcut for a program on the desktop, the user may use any of the
following methods. Click on the Start button on the taskbar to
display the start menu. Click on All Programs to display most of
the programs and right click on the desired program. Click on
(create shortcut) to send the program icon to the desktop.
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- APPLICATION WINDOWS Programs and folders open in their own
windows. These windows have certain characteristics in common. A
window is an area within a frame on the desktop screen in which a
program operates or information is displayed.
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- TYPES OF WINDOWS M ICROSOFT WORD A PPLICATION WINDOW F OLDER
WINDOW
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- THE TITLE BAR The title bar is a horizontal bar at the top of a
window. This bar contains the name of the program and control
buttons that are used to close or minimize the window.
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- Elements or features of the title bar
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- The title bar can be divided into two main sections. The first
section of the bar shows details of the program in use. A program
icon or logo is the first item. This is the logo that the makers of
the program have given the program as its unique identifier. The
second item on the title bar is the name of the active file. This
can also be called the file name or document name. Application
programs are used to create files and most programs we use create
files.
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- By default, when an application program is launched it create a
blank file with a temporary name until the user saves it with a
file name. The program name or application name/title is the last
part of the first section of the title bar. Control Box The second
section of the title bar is termed as the Control Box. This box
contains three buttons namely the minimize button the
maximize/restore button the close button
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- CONTROL BOX BUTTONS The minimize button The maximize
button/Restore button The Close button The Minimize button is used
to suspend or hide a window and reduce the window to a button on
the taskbar. This button also allows a user to keep a program
running in the background, so he/she can concentrate on other
things.
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- The Maximize/Restore Down button The Maximize is used to expand
a window to its biggest size possible. The Restore down button
replaces the Maximize button when a window is fully maximized. The
Close button The Close Button is used when a user want to close or
exit out of a window. This button closes a program and every file
that was open in that particular program.
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- THE CONTEXT MENU The Context Menu is a pop-up menu that appears
when you right-click on the title bar of a window. This menu gives
the user other ways of managing a window. Right-clicking on the
title bar of a window gives the user an additional way of
minimizing, maximizing/restoring, moving and closing a window.
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- LEARNING WITH ICT TOOLS Information and Communications
Technology tools have become a part of everything we do. From
health to education, entertainment and work and even in our
everyday social life, we make use of ICT. Learning with tools can
be done many ways. Students have been using these tools everyday in
their schools to assist them in accessing an sharing information.
Teachers also use them for the same purpose.
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- The following are the various ways ICT tools are use to learn.
Accessing information Sharing ideas Computing calculations Storing
information Processing and displaying information
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- How ICT tools Support Learning Learning is a term that is used
to describe a situation where a person or thing has acquired some
knowledge and is able to apply the it in situations that are able
to solve problems. Key issues in the learning process include
access to information and the medium that is used to communicate
such information. ICTs support learning in many different
areas.
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- Teaching In most formal educational set ups, learning is as a
results of structured teaching. ICTs are a big part of teaching.
Several different ICT tools available that are used in teaching.
There are tools such as overhead projectors, LCD projectors,
television, electronic boards, public address systems, and
computers which are directly used in transferring knowledge to
different students.
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- Teaching ICT tools LCD projector Overhead projector Projector
screen
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- Research Research is an important part of training. ICTs play a
very important role in research. In science, many new ways of
collecting and testing data has become possible because of ICT.
Unmanned mission to Mars has become possible because of ICT tools
like Opportunity,a robot, have successfully conducted experiments
and sent result to earth. Teachers and student alike are able to
have access to a lot of reading material through the internet.
Libraries are able to stock up with electronic journals, even when
they do not have the physical space to stock these volumes.
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- ICT tools for research Internet page Mars Rover
Opportunity
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- Knowledge Sharing Now more than ever before, learners from all
over the world are able to share ideas and information. Because of
I C Ts such as the internet, TV, radio and telephone, people are
able to get together easily to explore and debate in groups.
Learning has therefore become richer since there is the opportunity
to hear what people from completely different background have to
say about any particular issue. The use of mobile phones has become
extremely popular and common in all places.
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- Accessing Information The computer, television and radio are
some of the media through which information is made readily
accessible. It is particularly useful for students in deprived
areas since this comes at little or no cost. The Presidents special
Initiative on Education, for example, airs on national television.
The computer and Internet has also contributed and continues to
contribute immensely by providing easy access to information
through the help of internet search engines, which are tools that
allow you to search and find almost any type of in formation you
need. Information on educational CDs are also of immense use.
Software such as Encarta and Britannica are some examples.
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- Learner Support Learners need support and assistance as they go
through their learning process. ICT tools such as calculator, sound
recorders, computers and mobile phones provide this much needed
support. Complex mathematical calculations can be made easy and
simple by calculators, and important lectures may be recorded on
the audio recorder for future reference. Digital audio
recorders
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- School Administration A large part of learning takes place in
school. School administration provides the needed support to ensure
that learning goes on smoothly. This they do by scheduling classes,
registering students, compiling staff rosters and also any general
office administration such as typing letters and sending e-mails.
These duties are performed with tools such as computers, PDAs and
mobile phones.
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- Personal Digital Assistance
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- Simulation & Experiment One of the most exciting ways that
ICTs aid learning is in the area of experiment and simulation.
Several ICT tools (especially in the area of computers) have been
developed that can be used to simulate experiments that may be too
dangerous or expensive. These allow for students and trainees to go
though the learning experience without putting themselves in
danger. This method is sometimes used to train police drivers on
how to drive police cars.
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- PA systems Portable audio recorders Personal Digital
Assistance
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- SUMMARY NOTES It covers the following: HAZARDS Radiation Glare
Repetitive Strain Injury Contamination/Pollution Addiction
Electrical Shock and Fire outbreak SAFETY PRECAUTIONS IN THE USE OF
ICT TOOLS
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- RADIATION Radiation refers to a type of energy that is emitted
in the form of waves. These waves come from everyday ICT gadgets
that you use. The most common of these are mobile phones and
microwave ovens. Health experts suggest that long term exposure to
this type of radiation may lead to several health problems. These
problems include Headache Dizziness Nausea Sleep deprivation Cancer
Some ICT Tools that emit Radiation
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- GLARE Glare refers to over illumination or light pollution.
Most Visual Display Units (VDU) use high intensity light to display
images correctly. When you sit behind these screens for a long
time, our eyes get tired from the light that these screens emit.
Glare also results in health problems such as Headaches Eye
irritation Loss of eye sight.
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- Repetitive Strain Injury (RSI) Repetitive strain injury is a
health problem that is caused by the constant use of ICT tools.
This causes the muscles in the upper body to become sore as a
result of keeping them tense over long periods. When you perform
repetitive tasks over a long period the muscles become tired and
begin to ache. Computer users tend to suffer this symptom
regularly. This type of health is attributed to poor posture and
repetitive motions. RSI cause problems such as: Recurring pain or
soreness in neck, shoulders, upper back, wrists or hands. Tingling,
numbness, coldness, or loss of sensation. Loss of grip strength,
lack of endurance, and weakness. Muscles in the arms and shoulders
feel hard. Pain or numbness while lying in bed.
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- The diagram of the palm and wrist Typing for a long time causes
RSI. Using the mouse for long time causes RSI.
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- CONTAMINATION/POLLUTION Pollution is the introduction of
undesirable materials into the environment. Some ICT gadgets you
use produce contaminants constantly. Such contaminants may be
harmful to humans when inhaled. Laser printers and photocopiers
release toner into the atmosphere. These over a long period can
lead to disease. Some other gadgets also produce noise pollution.
Some of the problems that pollutants cause include: respiratory
disorders Cardiovascular (heart) problems Hearing loss High blood
pressure
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- Discarded computers that can cause contamination/pollution to
our health
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- ADDICTION Addiction can be explained as an obsessive and
uncontrollable need to use something. Because of exciting nature of
ICT tools, there is a growing problem of people becoming addicted
to them. There are millions of people who sit by the computers for
many hours and cannot get away from it, sometimes even to eat or
talk with their family members. Some symptoms of addiction are:
craving time to spend on gadgets over joy when at the computer
inability to stop ICT activity getting angry quickly when not using
ICT tools neglect of family and friends problems at work or
school
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- An addicted computer user
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- ELECTRICAL SHOCK/FIRE OUTBREAK Most ICT tools need some form of
power to operate well. There are a lot dangers associated with the
use of electricity. Faulty gadgets can lead to electrical shocks
that can harm humans. Also they can cause fire that can destroy a
lot of properties and kill humans
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- Safety Precautions in the use of ICT Tools Despite all the
problems enumerated above, ICT tools provide so much advantage and
use for us that you have to find a way to overcome these problems
and take advantage of the numerous services that ICTs provide.
RADIATION 1.Radiation can be reduced by constantly checking with
manufacturers for a newer version of our product that emit less
radiation.
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- The Radiation symbols
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- 2.We can also keep items that produce radiation farther away
from us. GLARE 1.Glare can greatly be reduced by acquiring anti
glare shields for computer screens. 2.Always adjust the brightness
level of the visual display unit to a level that your eyes will
tolerate. 3.Adjust your seating position so that you are not
sitting too close to the screen 4.Ensure there is proper lighting
in the room where you use ICT gadgets. 5.Take frequent breaks and
look at other things, so your eyes can take a well deserved
rest.
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- REPETITIVE STRAIN INJURY 1.Take frequent breaks and exercise
your hands and wrist. This will ensure proper circulation of blood
and muscle movement. 2.Place a writ rest between your keyboard and
the edge of your desk. 3.Dont place your mouse at the edge of the
desk. 4.Reduce the number of times that you have to take your hand
off the keyboard to the mouse
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- A diagram of correct position in front of the computer
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- Contamination/Pollution 1.Good ventilation is the key to
avoiding unnecessary exposure to pollutants. Where there is
adequate circulation, the risk of inhaling excessive pollutants is
reduced, since there is enough air to dissipate the concentration
of pollutants. 2.Check to make sure that your gadgets do not have
any leaks.
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- ADDICTION Addiction is very difficult vice to curb. Try not to
be pre-occupied by a tool all the time 1.Take breaks and attend to
other social issues 2.If you notice that somebody is staying on a
tool all the time, try to get them away for a while. Engage them in
conversation and draw their attention to your observation.
3.Experts be invited to assist those who are already addicted.
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- ELECTRICAL SHOCK AND FIRE HAZARDS In order to avoid electrical
problems and fire, you need to very cautious about how we connect
our gadgets. 1.Do not overload electrical sockets. 2.Avoid eating
and drinking near ICT tools.
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- GREEN COMPUTING Protecting the environment has become a very
important issue to human life. In Ghana, energy has become a vital
commodity in the last few years. It important to adopt healthy
measures in our use of ICT tools, to help conserve energy and hence
contribute to improve the energy situation. 1. When you are not
using computers, you need to make sure that they have been properly
turned off. 2. When buying new computers, you should ensure that
they comply with the Energy Star program a program that certifies
computers as energy efficient or not. 3. Print sparingly. Only
print items that you need and recycle paper as much as you
can.
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- INTERNET AND WORLD WIDE WEB(WWW) Internet is a world wide
interconnection of networks. Internet is a world wide collection of
networks that use the internet protocol (IP) to communicate with a
very powerful data transmission systems such as GPRS, Telephone
lines, Satellite, Modem and EDGE. A home computer may be linked to
the internet using a phone line modem, DSL or Cable Modem that
talks to an Internet Service Provider(ISP) such as ZipNet, Africa
On Line, Vodafone, MTN, Zain, etc. A computer in a business or
Collage will usually have a network interface card(NIC) that
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- directly connects to a local area network(LAN) inside the
business or use a modem which is connected to a telephone line.
ISPs then connect to a larger ISPs and the largest ISPs maintain
fiber-optic backbones for an entire nation or region. Backbones
around the world are connected through fibber-optic lines, undersea
cables or satellite links. The internet carry services such as file
transfer, online chat, email, and the popular World Wide Web.
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- It began in 1980s when physicist Dr. Berners-Lee wrote a small
computer program for his own personal use. This program allowed
pages, within his computer, to be linked together using keywords.
It soon became possible to link documents in different computers,
as long as they were connected to the internet. The document
formatting language used to link documents is called HTML(
Hypertext Markup Language) Prepared by Sir Lexis Oppong
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- The internet Figure 1.0: The Internet Connections The internet
Figure 1.0: The Internet Connections
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- WORLD WIDE WEB(WWW) The World Wide Web is an interconnection of
documents(called hypertext) across the internet. These web pages
may contain text, audio, images and video. Some times people use
the words Internet and World Wide Web(www) synonymously but they
are different. The WWW is a component of the internet that present
information in graphical interface while Internet is the physical
structure of the network. Prepared by Sir Lexis Oppong
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- The www refers to the only one resource a collection of
documents called web pages available through the internet. Figure
1.1: The World Wide Web Prepared by Lexis Oppong
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- ADVANTAGES OR USES OF THE WEB Performing research: The WWW
provides access to a vast amount of research material, including
resources from libraries, museums, and research institutions, i.e.
Microsoft Encarta. Chatting: Some online service providers enable
their users to talk in real time with each other while they are on
line through the use of chat room and instant messaging. Prepared
by Joachim Konyo
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- Obtaining News: Many media groups have website that provides
latest news headlines and newspaper reviews. Joy FM, Citi FM, Adom
FM, CNN, BBC are just a few examples. Downloading Software: The
availability of freeware, shareware and commercial software on the
internet makes it easy to download such wares from many website.
Distance learning: There are special courses on line from
universities and other centers of higher learning to be pursued
without the physical presence of the student at the campuses.
Arranging travel plans and checking exams results. Shopping: There
are website with links to online merchants that can meet your
needs. Indeed E- commerce has come to stay. Prepared by Sir Lexis
Oppong
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- WEB BROWSERS A web browser is a software designed to and view
web sites. A web browser translates HTML documents and allows you
to view web pages on your computer screen. Examples of web browsers
are Netscape Navigator, Safari, Opera, Firefox, Google chrome and
internet explorer.
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- Features of the Internet Web Browser Prepared by Sir Lexis
Oppong
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- Title Bar: The title bar contains the name of the web file you
have loaded, the name of the program used to load it and the
control button. The title bar FEATURES OF WEB SITE BROWSER Prepared
by Lexis Oppong
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- Navigation Bar The navigation bar allows a user to go back and
forth between web pages already visited. It contains two buttons
forward and back and a downward pointing arrow, used in a drop down
menu of the pages already visited. The navigation bar Prepared by
Sir Lexis Oppong
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- The Address Bar: The address bar provides the place where we
type a unique address of a page into. After typing the address, you
can either press enter or the arrow at the end of the bar to go to
the site. The address bar also has reload button that is used to
reload the page for the address written in the address bar. The
last icon on the bar is the stop button. Address Bar Prepared by
Sir Lexis Oppong
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- Menu Bar The menu bar contains commands that we issue to the
browser. These commands are grouped under headings such as File,
Edit and Help. Each menu has a drop down list of the individual
commands that can be used. Menu Bar Page Tab The page tabs in web
browsers allows users to view several different web pages in the
same window at the same time.
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- Prepared by Joachim Konyo Standard Toolbar : The standard
toolbar contains commands that are frequently used. Such commands
include print and save. The Tools Menu has some special functions
such as Cookie Manager Image Manager Password Manager Window
Help
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- Prepared by Joachim Konyo Content area: This is the part of the
explorer window that shows the content of the page you have
requested. The content page is usually made up of text, audio and
video. The are also special text called hyperlinks, that allow
users to move to other pages on the web when they are clicked
on.
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- Scroll Bar The scroll bar allows you to scroll up and down
through a particular page to have access to all of its content.
Scroll Bar The scroll bar allows you to scroll up and down through
a particular page to have access to all of its content.
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- Refresh or Reload button It refreshes the currently displayed
page with a newer version of the same page. It is usually when a
page is not well displayed. Refresh or Reload button It refreshes
the currently displayed page with a newer version of the same page.
It is usually when a page is not well displayed.
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- Status Bar The status bar provides information and statistics
about a particular page that you have visited.
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- The Homepage The homepage is the page that a user sets in his
browser settings that tells the computer to load that page every
time the browser is opened. The first page you visit when you load
a browser may differ. Picture of Google Homepage
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- LAUNCH AND EXIT FROM A WEB PAGE A web page is a sample text
file that contains not only text, but also a set of HTML tags that
describe how text should be formatted when a browser displays it on
a screen (HTML- HTML stands for Hyper Text Markup Language. A
markup language is a computer language that describes how a page
should be formatted). The tags are simple instructions that tell
the browser to do things like change the font size or colour, or
arrange things in columns. Launching A Web page Viewing a web page
on the World Wide Web normally begins by typing the Uniform
Resource Locator (URL) or website address of the page into a web
browser or by following a hyperlink to pages. The web browser then
initiate a series of communication messages, behind the scenes, in
order to fetch and display it.
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- First, the server- name portion of the URL is resolved into an
IP address using the global, distributed Internet database known as
the Domain Name System or DNS. This IP address is necessary to
contact and send data packets to the Web server. The browser then
requests the resource by sending an HTTP request to the Web server
at the particular address. Having received the required file from
the Web server, the browser then renders the page onto the screen
as specified by its HTML, CSS(Cascading Style Sheet) and other Web
languages. Any images and other resources are incorporated to
produce the on - screen Web page that the user sees. Most Web page
will themselves contain Hyperlinks to other related pages.
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- STEPS TO LAUNCH A WEB PAGE Assuming the URL or website address
is http://www.cosmosschool.com/?_alias=home& 1.Launch the web
browser you want to use to browse 2.Type the address in the address
bar 3.Press ENTER button Address bar
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- COSMOS SCHOOL WEBSITE HOME PAGE
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- Exiting a web page Exiting or closing a web page is as simple
as closing any other window. Clicking the close button on the title
bar closes an application. You can also exit a web page or site by
using the File menu on the Menu bar. Click on the File menu for a
drop down sub-menu. Scroll down the menu until your mouse pointer
can rest on Exit. Click on it to close the window
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- Some important abbreviations TCP/IP: Transmission Control
Protocol/Internet Protocol. FTP: File Transfer Protocol SMTP:
Simple Mail Transfer Protocol. HTTP: Hypertext Transfer Protocol.
HTML: Hypertext Mark-up Language. Prepared by Joachim Konyo
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- Advantages and Disadvantages of the Internet Advantages of the
Internet Communication The internet has helped us communicate
quickly and effectively. The use of e-mail has cut down
considerably on the cost and time that it takes to send messages
across to people. It is even possible to communicate via audio and
video.
- Slide 109
- Education Schools and institutions are now able to share
educational resources more than ever before. Virtual classrooms and
correspondence courses have allowed for more people to have access
to quality education.
- Slide 110
- Information The internet and World Wide Web are full of
information. There are resources on every field available on the
internet. This makes easy to source for information. It saves time
as one does not have to physically move many places to gather
data.
- Slide 111
- Business Business organizations are benefiting immensely from
the internet. There are now many online shops that sell goods and
services over the internet.
- Slide 112
- Government National governments and their dependent agencies
are now able to communicate with their citizens and indeed other
countries about new developments in the country.
- Slide 113
- Entertainment Radio and television stations are able to reach
their audience all over the world. Individuals are able to have
access to music and TV shows that are not usually available in
their physical location.
- Slide 114
- Disadvantages of the Internet Cost The cost of internet and its
facilities is very expensive. This leads to a situation where those
who do not have money, cannot benefit from the use of the internet.
Fraud Internet has also brought a new breed of crime. Identity
theft is a situation where some unscrupulous individuals steal the
personal details of unsuspecting people and are able to impersonate
and steal their money. Virus attacks Internet connections have
allowed for computer viruses and malware to spread more quickly and
easily. Computer virus such as Trojan horse spreads through the
internet.
- Slide 115
- Misinformation People upload data and information onto the
internet which are not accurate since no one person owns the
internet. Therefore, not everything you read on the internet is a
fact.
- Slide 116
- Most connections to the internet are done through the use of
computers.
- Slide 117
- MOBILE DEVICES Mobile devices such as cell phones, Personal
Digital Assistants(PDAs), handheld game consoles, smart phones,
pagers and LED televisions also use the internet.
- Slide 118
- TECHNOLOGIES USED TECHNOLOGIES TO ACCESS THE INTERNET Internet
is a network of networks. It is a huge environment - a collection
of technologies involved in the Internet. Now, let us see some of
the ways to get connected to the Internet to access its huge
resource areas. So many technologies are used to access the
Internet. They are:
- Slide 119
- DIAL-UP CONNECTION A dial-up connection uses the analog
telephone line for establishing a temporary communication.
Computers digital signals must be converted to analog signals
before they are transmitted over standard telephone lines. This
conversion is performed by a Modem. Modem is a Modulator
Demodulator. It converts computer digital signal into analog signal
which is suitable for the transmission over a telephone line and
vice versa. Both the sending and the receiving ends of a
communication channel must have a Modem for data transmission to
occur. Using a dial-up line to transmit data is similar to using
the telephone to make a call. Computer digital signal is a basic
signal, which is regulated by electric current, used for computer
communication.
- Slide 120
- The client computer modem dials the pre-programmed phone number
for a users Internet Service Provider (ISP) and connects to one of
the ISPs modems. After the ISP has verified the users account, a
connection is established and data can be transmitted. When either
of the modems hangs up, the communication ends. The advantage of
dial-up line is that it costs no more than a local telephone call.
A dial-up connection using a telephone line A Modem
- Slide 121
- ISDNs (Integrated Services Digital Networks) are special
digital telephone lines that can be used to dial into the Internet
speeds ranging from 64 to 128 kbps. These types of connections are
not available everywhere. Telephone companies have to install IDSN
digital switching equipment. IDSNs require the use of a special
digital modem that sends and receives digital signals over IDSN
lines. ISDN ISDN Connection
- Slide 122
- Currently, most households with cable TV have the option for
cable modem Internet access. The cable modem offers a high-speed
link at low cost for unlimited access. The connection speeds range
from 128 Kbps to 10 Mbps (megabytes per second). A cable modem is a
device that connects to the existing TV cable feed and to an
Ethernet network card in the users PC (also called an NIC Network
Interface Card). CABLE MODEM Cable modem
- Slide 123
- DSL DSL service is a high-speed data service that works over
POTS (Plain Old Telephone Service) copper telephone lines and is
typically offered by telephone companies without costly
installation of a higher-grade cable. ADSL (Asymmetric DSL) is the
type of DSL that provides different bandwidths in the upstream and
downstream directions. SDL (Symmetric DSL) offers the same
bandwidth capability in both directions.
- Slide 124
- DSL modem set up
- Slide 125
- SATELLITE CONNECTION Getting the Internet feed from a satellite
is not completely different from getting TV signals from one. In
both cases, data is being sent from the satellite to a users
equipment and then translated and decoded. One major limitation of
satellite technology is that it can only send data from the
satellite to a users receiver not the other way. To get around this
problem, a separate ISP connection is needed to send data to the
Internet, typically over an analog modem. This connection works in
conjunction with the satellite feed.
- Slide 126
- Internet via Satellite
- Slide 127
- TELEPHONE LINE Modems do not need a special telephone line;
instead one can use the regular telephone line for the Internet.
However, the drawback of such an arrangement is that the phone
cannot be used to make or receive other calls, while the computer
is using it. Telephone line set up
- Slide 128
- GPRS GPRS (General Packet Radio Service) is a packet based
communication service for mobile devices that allows data to be
sent and received across a mobile telephone network. GPRS is a step
towards 3G and is often referred to as 2.5G.
- Slide 129
- EDGE EDGE (Enhanced Data rates for GSM Evolution) is an
evolution to the GSM mobile cellular phone system. The name Edge
STANDS FOR Enhanced Data for GSM Evolution and it enables data to
be sent over a GSM TDMA system at speeds up to 384 Kbps. EDGE
evolution is intended to build on the enhancements provided by the
addition of GPRS where packet switching is applied to a
network
- Slide 130
- Internet Service Provider An Internet Service Provider (ISP) is
a business organization that provides access to the Internet and
related services for the customer. Speed of an Internet connection
can be divided into two categories: dial-up and broadband. Dial-up
connections require the use of a phone line and usually have
connection speeds 56 Kbps or less. Broadband connections can be
broadband wireless access, cable modem, fiber optics, satellite or
Ethernet. Broadband speed varies between 64 Kb and 20 Mb per
second.
- Slide 131
- ISPs in Ghana There are several ISPs in Ghana. Some of them are
as follows: Africa Online Ghana Limited Network Computer Systems
Wireless Ghana INTERNET Ghana RapidCloud Technology Ltd Redline
Communications NetSAT Ltd iBurst Broadband4U DSL@InternetGHANA
Zipnet Broadband Africanus.net
- Slide 132
- Internet Service Providers in Ghana
- Slide 133
- CURRENT TECHNOLOGY Current Technology in Computer Networks (A)
Wi-Fi Official Wi-Fi logo Wi-Fi (wireless fidelity) is a set of
standards that refers to the Wireless Local Area Network (WLAN)
that applies IEEE 802.11 specification.
- Slide 134
- A computers wireless adapter translates data into a radio
signal and transmits it using an 3antenna. A wireless router
receives the signal and 4decodes it. It sends the information to
the internet using a physical, wired Ethernet connection. To
receive the signal, the router will receive data from the Internet,
translating it into a radio signal and sending it back to the
wireless adapter.
- Slide 135
- 1. Simplicity. You can connect computers anywhere in your home
or school without the use for wires. Computers connected to the
network using radio signals and computers can be up to 30 meters or
so apart. 2. Cost Wireless Networks are easy to set up and are
inexpensive. 3. Easy Access Wi-Fi supports 1roaming by moving your
computers from one access point to another as you move around a
2hot spot. Wi-Fi works like a two-way radio communication. Some of
the advantages of using Wi-Fi are as follows:
- Slide 136
- Bluetooth logo Bluetooth Headset B. Bluetooth Bluetooth is a
network standard, specifically a protocol that defines how two
Bluetooth devices use short-range radio waves to transmit data. The
data transfers between the devices at a rate of up to 2 Mbps. To
communicate with each other, Bluetooth devices must be within 10
metres but can be extended to 100 metres with additional
equipment.
- Slide 137
- A Bluetooth device contains a small chip that allows it to
communicate with another Bluetooth device. Examples of
Bluetooth-enabled devices are desktop computers, notebook
computers, handheld computers, PDAs, smart phones, headset,
microphones, digital cameras, fax machines and printers.