2. 1. Introduction
Definition of ICT
• ICT – Information and Communication
Technology
• It is a merger of two technologies:
– Information Technology – storage and processing of
data using computers.
– Communication Technology – high speed transmission
of data (messages).
• ICT also refers to the merger of audio-visual
and telephone networks with computer
networks through a single cabling or link.
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3. Components of ICT
• ICT refers to technologies that provide access to
information through telecommunications
• It is similar to Information Technology (IT), but
focuses primarily on communication
technologies. This includes the Internet,
wireless networks, cell phones, and other
communication media.
4. Data vs Information
• One of the primary goals of information systems
is to economically process data into information
and knowledge
• Data items refer to an elementary description of
things, events, activities, and transactions that
are recorded, classified, and stored but are not
organized to convey any specific meaning. Can be
numbers, letters, figures, sounds, or images.
• Information refers to data that have been
organized so that they have meaning and value to
the recipient.
5. Data vs Information
• Knowledge consists of data and/or information
that have been organized and processed to
convey understanding, experience, accumulated
learning, and expertise as they apply to a current
business problem. For example, a company
recruiting at your school Based on its experience,
that company may decide to interview only those
students with GPAs over 3.0. Organizational
knowledge, which reflects the experience and
expertise of many people, has great value to all
employees.
6. Characteristics of Valuable
Information
• All the information is not helpful to a business or
an organization. What are the main features of a
good quality information in a business or an
organization?
– Relevant
– Up-to-date
– Accurate
– Meet the needs of the user
– Easy to use and understand
– Worth the cost
7. Characteristics of Valuable
Information
• In order for information to be valuable, it must have the following
characteristics:
1. Accurate. Accurate information is free from error.
2. Complete. Complete information contains all of the important facts.
3. Economical. Information should be relatively inexpensive to
produce.
4. Flexible. Flexible information can be used for a variety of purposes,
not just one.
5. Reliable. Reliable information is dependable information.
6. Relevant. Relevant information is important to the decision-maker.
7. Simple. Information should be simple to find and understand.
8. Timely. Timely information is readily available when needed.
9. Verifiable. Verifiable information can be checked to make sure it is
accurate.
8. Types of Computers
Computers are classified based on different
criteria:
• Based on their purposes:
– General-purpose – used for a variety of tasks
• E.g. the PCs in wide use in our labs and Internet cafés
– Special-purpose – perform specific tasks.
• E.g a computer that guides a missile
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9. Types of Computers (cont’d)
• Based on the data they handle:
–Analog computers process analog data.
• By analog, we mean continuously varying quantity.
– Digital computers process digital data.
• Digital data assume one of two values, 1 (high) or 0
(low).
–Hybrid computers exhibit features of analog
and digital computers.
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10. Types of Computers (cont’d)
Based on the size or function
• Super computers
– Most powerful and expensive
– Used for problems requiring complex
operations (e.g. tracking spaceship, weather)
• Mainframe computers
– Capable of great processing speeds and data
storage
– Not as powerful as supercomputers
– Housed in special rooms with special power
and environmental control.
– They are used as e-commerce servers
handling transactions over the Internet
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11. Types of Computers (cont’d)
• Minicomputers
– Known as midrange computers
– Medium-size companies
– Used by departments of large
companies
• Microcomputers
– Least powerful
– Widely used
– Four types
• Desktop
• Notebook or laptop
• Tablet PC
• Handheld
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12. Characteristics of computers
A computers has the following characteristics:
– It is automatic
– It is extremely fast
– It is highly accurate
– It is diligent
– It is highly versatile
– It has high power of remembering
– It has no IQ
– It has no feeling
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13. Application Areas of Computers
• Computers are applied in almost all areas, including:
– Business – E.g. payroll calculations, sales analysis, financial
forecasting, managing employees database, etc.)
– Banking – E.g. likeonline accounting facility, ATM machines, etc)
– Insurance - to maintain a database of all clients with information
showing procedure to continue with policies, starting date of the
policies, next due installment of a policy, maturity date, interests
due, survival benefits, bonus, etc.
– Education – E.g. Computer Based Education, which involves
control, delivery, and evaluation of learning; assisting in
searching information.
– Marketing – E.g. advertising, home shopping, etc.
– Health Care – E.g. diagnostic system, patient-monitoring system,
pharma information system, surgery, etc.
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14. Application Areas of Computers
(Cont’d)
– Engineering Design – Examples include:
• Structural Engineering - stress and strain analysis for design of
ships, buildings, bridges, airplanes, etc.
• Industrial Engineering - design, implementation and improvement
of integrated systems of people, materials and equipments.
• Architectural Engineering - planning towns, designing buildings,
determining a range of buildings on a site using both 2D and 3D
drawings.
– Military – e.g. missile control, military communication,
military operation and planning, smart weapons, etc.
– Communication – E.g. E-mail, Chatting, FTP, Telnet, Video-
conferencing, etc.
– Government - E.g. Budgets, Sales tax, Income tax,
Male/Female ratio, Computerization of voters lists,
Computerization of driving licensing system,
Computerization of PAN card, Weather forecasting, etc.14
15. 3. The Computer System
• A complete computer system includes four
distinct parts: Hardware, Software, Data and
Users.
• Data – raw facts to be processed by computer.
– Includes numbers, text, images, audio or video
– All data are represented as strings of bits.
– Data is processed to produce information.
• Users – people operating the computers.
Computer System Components
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16. Computer System Components (cont’d)
• Hardware – Physical components that you can
touch or feel. It consists of:
– The system unit which houses the motherboard,
microprocessor, power supply, memory, etc.
– The keyboard, monitor, and mouse.
– Other peripheral devices like printer, digital
camera, scanner, LCD projector, etc.
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17. Computer System Components (cont’d)
• Software or program is a set of detailed
instructions that tell the computer what to do.
– A software may come in different media, but at
the time of running, it is loaded onto memory.
– A processor fetches an instruction from memory,
decodes it and then executes the required
operation.
– When an instruction has been executed the next
instruction is fetched, decoded and executed, etc.
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18. 7. The Internet
– Global Interconnection of networks and computers
– No owner of Internet; only standards bodies
– Internet access is through ISP (Internet Service
Provider)
– Internet access technologies include:
• Non-permanent (dial-up) connection
– Uses MODEM and telephone lines
• Permanent – connection, which includes:
– DSL (digital subscriber line – using telephone lines)
– Coaxial cable
– Fiber-optic
– Wireless
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19. The Internet (cont’d)
• To establish dial-up connection, you need:
– An account with an ISP
– A telephone connection
– Modem (MOdulator/DEModulator)
– Communication software (e.g. Internet browsers such
as Internet Explorer and Mozilla Firefox)
• Advantages of dial-up connection:
– Is not costly to connect
– It flexible
– Small monthly payment
• Disadvantage
– Low speed and connection set-up time
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20. The Internet (cont’d)
• Advantages of the permanent connection
– Faster speed
– Fixed monthly payment
• Disadvantages of the permanent connection
– Higher cost than dial-up
– Not flexible, except for the wireless
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21. BASICS OF PREVENTIVE
MAINTENANCE
• A computer may hang; send error messages, or
worse, no longer work at all.
• If you know how to troubleshoot problems
related to a computer, you can save hundreds or
even thousands of Birrs.
Environment and Location of a Computer
• Computer is a very sensitive device and needs to
be placed very carefully.
• you must take into consideration that dust-free
environment and proper location are maintained
for it.
22. BASICS OF PREVENTIVE
MAINTENANCE
• You must take care of the following:
– Always place your computer in an open area that
allows adequate airflow.
– Keep the computer in a cool, dry and dust-free
environment.
– Keep level, stable floors and tables.
– Arrange ergonomic furniture.
– Keep precautionary fire prevention equipment.
– Must have static electricity.
– Keep the computer safe from vibrations.
23. BASICS OF PREVENTIVE
MAINTENANCE
Electric Power
• it can harm a PC or its data if it does not flow properly.
• Let us understand some of the causes of power
problems.
– A brownout occurs when the supply of electricity drops
dramatically
– Blackouts occur when power goes out completely.
– Power spikes or power surges occur when the voltage on
your power line rises suddenly to above-normal levels,
Power spikes are extremely dangerous and can destroy PCs,
monitors, and any other component plugged into the
affected power line.
– Lightning storms are an underrated hazard.
24. Backup Methods
• There are different methods for backing up data
stored in files. Some of the best and most secure
methods are:
– External hard drives
– Flash drives/USB thumb drives
– Remote data storage via the Internet
– CD/DVD-ROMs
Manual
• Update anti-virus program
• Back-up hard drive
• Test electrical surge protector
25. Using Utility Programs
• Backup
• Data-recovery
• Virus protection
• Data compression
Improving Hard Disk Performance
• The following steps will help you to improve hard disk performance:
– (i) Remove duplicate files from hard disk.
– (ii) Remove temporary files.
– (iii) Hive off the non-essential files.
– (a) Find large files occupying your disk space.
– (b) Store all these files online.
– (iv) Defragment hard disk.
– (v) Detect and repair disk errors.
26. To keep your computer running smoothly and
to ensure that it has a long and productive life,
follow the following tips.
• Keeping your system free of dust, dirt and
liquids.
– Never spray your monitor screen with glass
cleaner. Instead, spray a lint-free cloth lightly
with glass cleaner, and then clean the screen.
– Clean keyboards, computer case vents, or
around disk drive openings using canned air or
small computer-specific vacuum cleaners.
Computer Care and Safety
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27. –Clean the rubber ball inside the bottom of a
mouse occasionally.
–Never try to remove the cover on your
computer to clean inside. Instead, take it to
an authorized service technician for
cleaning.
–Keep all liquids and food items away from
your computer.
–Wipe off the keyboard keys with a soft cloth
dampened with rubbing alcohol.
Computer Care and Safety (Cont’d)
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28. • Keep the computer away from heat sources
(like radiators and heat registers).
• Never use your computer during a storm. Also
use surge arresters.
• Protect your computer from viruses/worms.
– Install, use and regularly update virus software
– Never open an email attachment unless you know
and trust the person who sent it.
– Do not accept downloads from Internet sites that
you don't know and trust.
Computer Care and Safety (Cont’d)
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29. • Avoid installing several programs one right
after the other.
– try installing one program, then use your
computer long enough to see how your system
responds to the installation before loading the
next program.
• Keep CDs away from dust, liquids, or other
damaging or corrosive substances.
– If you have problems with CDs, buy a CD
cleaner and read the instructions carefully.
Computer Care and Safety (Cont’d)
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