Introduction to computer

1. Application of ICT in Adult
Teaching and Learning
Module Code: MAU07102
Expectations:
• Active participation in all lectures, group
discussion, seminars and lab sessions
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2. Assessment
• Continuous Assessment – 50%
Classroom Test- 10%
Mid Semester Test – 15%
Participation – 5%
Project/Individual assignment – 10%
Portfolio – 10%
• End of Semester Examination – 50%
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3. Course Overview
• Computer Basics & Computer system
– Computer Hardware
– Computer Networks
– System & Application Software
• Generic Software
– MS Office, Spreedsheet, Databases
– Managing information in Adult
Education Programmes
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4. Course Overview ….
• Internet
– Internet basics
– Internet in Education
– Search and browsing
• ICT in Teaching and learning
-ICT in Education
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5. What is a computer?
A computer is
– an electronic
device that inputs
data, processes
data, displays
information and
stores
information
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6. Computer Systems
We usually refer to ‘a computer’.
However,
•A computer consists of many
components, assembled to make
a whole system, hence, computer
system
• The components helps to
perform information- processing
tasks
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7. Different Parts of Computer
• Input devices (e.g keyboard, mouse etc)
• Processing devices (e.g CPU-Central
Processing Unit)
• Storage devices (e.g Hard Disk, flash disk, CD,
DVD etc
• Output devices (e.g Printer, Monitor or
computer screen, Speaker)
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8. Different Parts of Computer
OUTPUT DEVICE e.g. Monitor
PROCESSING DEVICE e.g.
CPU-Central Processing Unit
OUTPUT DEVICE e.g. Speaker
INPUT DEVICE e.g. Keyboard
INPUT DEVICE e.g. Mouse
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9. TYPES OF COMPUTERS
1. Supercomputers- most powerful and
used by large organisations eg. NASAspace exploration
2. Mainframe Computers – powerful (have
great processing speed and data storage)
eg. Used by insurance companies
3. Minicomputers (Midrange computers)refrigerator size e.g used by medium size
companies or depts of large companies
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10. 4. Microcomputers – least powerful, but
widely used and fastest growing type
• Types
a.Desktop Pcs – small to fit on top of
or alongside the desk, too heavy to
carry around
b.Notebook (Laptop) computersportable & fit into most briefcases
c.Tablet Pcs – cf laptop, but accepts
handwriting that is converted to
standard text eg. MS Word
d. Handheld(Palm) Pcs–the smallest
& designed to fit into one’s hand eg.
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PDA, mobile phones

11. Representing information
• Information can be
represented as analogue
or digital data
• Computers use digital
data
Analogue
information –
continuous variable
e.g. Voicecontinuous signals
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Digital
information –
discrete steps
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12. Example – clocks
An analogue
clock has hands
that can be in
any position
around the dial
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A digital clock
moves from one
second to the next
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in steps

13. Computers use digits
(numbers) to process data
•Characteristics (colour, sound,
text) are represented by numbers.
•Numbers are easier to work with
electronically
•Numbers can be stored and
transmitted more accurately
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14. Binary System
• Bi (Latin) = 2
•The counting system in which all
numbers consist of only two digits (0 & 1)
i.e. The binary counting system has only
two values, 0 and 1, represented
electronically as different voltage levels
(On/Off).
Computers are digital devices working in the
binary number system.
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15. Some examples of binary numbers
• Each digit in a binary system is
called a bit (binary digit)
• A group of 8 bits is called a
byte.
• A byte will represent a letter,
number, or character
e.g. (A=0100 0001, 1=0011 0001,
$=0010 0100)
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16. Forms of Data Inputs to
Computers
• Data inputs can be either in digital or
analogue form
• Sound
• Graphics
• Video
• Text
• Numeric
Note: Before any processing can take
place, the computer will convert
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analogue data into digital data

17. Binary Coding Schemes
1. ASCII(American Standard Code for
Information Interchange) is an older
standard. Originally only 7 bits were used to
represent each character, allowing for 128
different characters.
2. EBCDIC (Extended Binary Coded Decimal
Interchange Code) cf IBM
For example:
ASCII
EBCDIC
1
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0011 0001
1111 0001
A
0100 0001
1100 0001
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18. 3. Unicode
• The current standard used around
the world with sixteen bits used for
each character, giving over 64,000
different characters that can be
represented.
• Hence, easy to code languages with
many characters
E.g.
Chinese and Japanese
• The first 128 characters of the
Unicode set are the same as ASCII.
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19. Characteristics of Computers
Speed
The computer was invented as a high speed calculator. For example
if we want tomorrow’s forecast today (and not in six months time)
meteorologists can use the computer to perform quickly the
necessary calculations and analyses
Accuracy
The computer’s accuracy is consistently high. Please note here that,
the errors in computing are due to human rather than to
technological weaknesses of the computer itself
Diligence
Being a machine, a computer does not suffer from the human traits
of tiredness and lack of concentration. For example if 3 million
calculations have to be performed, it will perform the 3 millionth
with exactly the same accuracy and speed as the first.
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20. Characteristics of Computers….
Automation
A computer is much more than an adding machine, calculator or
check-out till, all of which require human operators to press the
necessary keys for the operations to be performed. Once a program
is in the computer’s memory, the individual instructions re hen
transferred, one after the other, to the control unit for execution.
Versatility
Computers can perform multiple tasks of different nature at one
and the same time. For example, one can write an article in MS
word on computer while listening online music and at the same
computer print outs of some documents simultaneously.
Storage
Computer have the ability to storing large amount of data. For
example, once can stored trading materials of hundred of books on
one DVD which otherwise may occupy one room for storage.
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21. How a Computer Functions
• Accepts Data (INPUT)
• Process Data (PROCESSING)
• Produces Output (OUTPUT)
• Stores Results (STORAGE)
Note:
These are the main functions of computer as well
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23. How is this tied together?
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24. Hardware and Software
• Hardware refers to the physical components of a
computer system – the system unit and all its
contents, the keyboard, mouse, monitor, etc.
• Software refers to the information – programs and
data that the computer uses
• Information must also be stored in some physical
way. The disks, flash memory devices, tapes etc
that software comes on are generally referred to as
‘media’
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25. PC Hardware consists of
• The System Unit
which is a case with a power supply
and other internal components,
connections at the back and drives in
the front
• Attached devices
called peripherals, generally
including a monitor, keyboard and
mouse, and maybe a modem,
printer, scanner, etc.
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26. A typical PC may contain
• 2.4 GHz Pentium 4
Processor
• 512 MB RAM
• 80 GB Hard Disk
• 52x speed CD ROM Drive
• 17” LCD Multimedia Video
Display with 1280 x 1024
resolution
• 56 KB Modem or Network
Card
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What do all these mean?
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27. The System Unit contains
•
•
•
•
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Motherboard
Power Supply • Hard disk drive
CPU
• Floppy Disk Drive
RAM
• CD-ROM
• Expansion cards
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28. PCI expansion slots
Slot for graphics card
CPU socket
Memory slots
Gigabyte motherboard for the Intel P4 processor
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29. Motherboard
has the electrical
highways (bus)
printed on it
has BIOS chip
has CMOS chip
(sometimes in with
the BIOS)
Controllers for
memory and other
hardware
Socket for
connecting CPU
Slots for expansion
cards
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CMOS-complementary metal oxide semiconductor BIOS-Basic input/output system

30. Motherboard Components
A bus
•an ‘electrical highway’ consisting of
many lanes.
•Data moves along these tracks
between the CPU and memory, to
storage devices and other hardware
More lanes means faster processing.
e.g. The Pentium 4
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uses a 64-bit data bus.

31. BIOS
a Read-Only Memory chip which
stores the instructions the computer
needs when it first starts, and
instructions to communicate with
hardware.
Note
ROM is not lost when the power is
off, so this is always available to the
CPU.
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32. BIOS
•Its first job is to check the hardware.
•This is referred to as the Power-On SelfTest (POST).
•Next, the BIOS must start loading the
Operating System from disk, which
takes over running the computer.
•This phase is called the Initial Program
Load (IPL).
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33. CPU – Central Processing Unit
• The ‘brain’ of
the computer.
• Performs
arithmetic,
logical and
decision
making
operations
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Intel Pentium 4 CPU
with cooling fan
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34. CPU Characteristics
• CPUs (microprocessors) used in PCs
generally use 32 bit numbers
• They run at a speed determined by the
clock. For Intel CPUs (e.g. Pentium 4)
this is currently 2 – 3.6 GHz, but gets
faster every year
• CPU producers:
• AMD
• Intel.
• Motorola produces CPUs, used in Apple
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and Macintosh computers

35. Big Numbers
• Kilo means a thousand 1 000
In binary, 210 or 1024 is pretty close to
kilo
• Mega means a million 1 000 000
In binary 220 or 1 048 576 is pretty
close to Mega
• Giga means billion 1 000 000 000
2 GHz (2 GigaHertz) means
2 000 000 000 clock cycles every
second – very fast!
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