This document provides an introduction to computing concepts for students pursuing a National Diploma. It begins with biographical information about the author and an overview of the course objectives. The core concepts covered include the history of computers, hardware and software components, computer memory, input/output devices, data storage, how computers work, operating systems, applications software, data processing techniques, data communication and computer networks, the internet, and the social impact of computers. Diagrams and definitions are provided to explain each topic at a basic level.

1. INTRODUCTION TO COMPUTING
COM 101
FOR NATIONAL DIPLOMA STUDENTS
By
Murtala Lawal Kazaure
Hussaini Adamu Federal Polytechnic
Kazaure, Jigawa State

2. Self Introduction
BIOGRAPHICAL DATA
• Who : Murtala Lawal
• When: 18th November
• Where: Kazaure, Jigawa State
• Pri: Magwan Special Primary School 1985-1991
• JSS: GSS Kazaure 1991-1994
• SSS: Science College Lautai Gumel 1994-1997
• B.Sc.: Usman Danfodio University Sokoto 2001-2006
• M.M : Multimedia University Malaysia 2013-2014
• CCNA: BUK Local Academy 2010
• C-Tech CI : Informatics Institute Kazaure 2006

3. This course is designed to enable
students to acquire a BASIC
KNOWLEDGE OF COMPUTERS

4. On completion of this course the diplomat, should be able to:
1. Understand the history, classification and impact of computers
2. Know the concept of computer hardware
3. Know the concept of computer software
4. Understand computer data processing systems
5. Know the procedures for computer and data preparation method
6. Understand security and safety procedures within a computer environment
7. Understand the concept of a computer network
8. Understand the use of the internet

5. WHAT IS COMPUTER ?
Computer is an ELECTRONIC
machine/device that accept
DATA as an INPUT, PROCESS
it and gives out
INFORMATION as an
OUTPUT.

6. BASIC FUNCTIONS OF COMPUTER

7. Main Parts of a Personal Computer
• The System Unit
• The System (Mother) Board
• The CPU (Central Processing Unit)
• Memory RAM
• Memory ROM-BIOS
• Keyboard
• Mouse
• Visual Display Unit

8. The System Unit

9. Motherboards

10. The CPU
Central
Processing
Unit

11. Memory RAM

12. Memory ROM-BIOS

13. Keyboard

14. Mouse

15. Visual Display Unit

16. Know how computer memory is measured
• Basic Units of Data Storage = Bit
• Bit = 1 or 0
• 8 bits = 1 byte
• Kilobyte (KB) = 1024 bytes
• Megabyte (MB)= 1024 kilobytes, approximately 1,000,000 bytes
• Gigabyte (GB)= 1024 megabytes, approximately 1,000,000,000 bytes
• Terabyte (TB) = 1024 gigabyte, approximately 1,000,000,000,000 bytes

17. Speed
Accuracy
Storage
Consistency
Repetitiveness
Complexity

18. THE FIVE GENERATIONS OF COMPUTER
• First Generation - 1940-1956: Vacuum Tubes
• Second Generation - 1956-1963: Transistors
• Third Generation - 1964-1971: Integrated Circuits
• Fourth Generation - 1971-Present: Microprocessors
• Fifth Generation - Present and Beyond: Artificial Intelligence

19. First Generation - 1940-1956
Vacuum Tubes

20. Second Generation - 1956-1963

21. Third Generation - 1964-1971
Integrated Circuit

22. Fourth Generation - 1971-Present
Microprocessor

23. Fifth Generation - Present and Beyond
Artificial Intelligence

24. BRIEF HISTORY OF COMPUTERS
Computer was originally a job title
Abacus: an early aid for mathematical computations
Pascaline: A gear-driven one-function calculator invented by Blaise Pascal

25. BRIEF HISTORY OF COMPUTERS
EDSAC : Electronic Delay Storage Automatic Calculator
Jacquard loom: The first programmable devices
Z3 the first working machine featuring binary arithmetic
Atanasoff–Berry Computer

26. BRIEF HISTORY OF COMPUTERS
British Colossus Computer
Harvard Mark I
ENIAC (1946): Electronic Numerical Integrator And Computer

27. CLASSES OF COMPUTERS
Computers can be classified based on the following parameters:
• Type of data processed
• The size
• The Purpose or scope
• The age of technology

28. Classification of Computers according to the type of data they processed.
• Digital computers
• Analog computers
• Hybrid computers

29. Digital computers

30. Analog computers

31. Hybrid computers

32. Classification by Purpose or Scope
Using scope as a criterion, computers can be classified into two
broad categories:
• Dedicated or Special purpose computers
• General Purpose Computers

33. Dedicated or Special purpose computers

34. General Purpose Computers

35. Classification by Size
Using physical size as a factor, the following types of computers can
be identified:
• Micro-Computers
• Mini Computers
• Mainframe Computers

36. Micro-Computers

37. Mini Computers

38. Mainframe/ Super Computers

39. INPUT DEVICES AND THEIR FUNCTIONS
An input device is any
peripheral (piece of
computer hardware
equipment) used to provide
data and control signals to
an information processing
system (such as a
computer).

40. Keyboards

41. Pointing devices

42. High-degree of freedom input devices

43. Composite devices

44. Audio Input Devices

45. Medical Imaging devices

46. OUTPUT DEVICES AND THEIR FUNCTIONS
An output device is any piece
of computer hardware
equipment used to
communicate the results of
data processing carried out by
an information processing
system (such as a computer)
to the outside world

47. Visual Display Units

48. Speakers

49. Printers

50. Electrostatic Printers

51. Thermal Printers

52. Projectors

53. Holographic Display

54. COMPUTER STORAGE
Computer components,
devices, and recording media
that retain digital data used for
computing for some interval of
time

55. Primary Storage
Memory directly accessible to
the CPU

56. Secondary Storage

57. Purpose of storage
Storing Operating Instructions and Data

58. Off-line storage
Is a computer data
storage on
a medium or a device
that is not under the
control of a
processing unit

59. Characteristics of storage
• Volatility
• Differentiation
• Mutability
• Read only storage
• Slow write, fast read storage
• Accessibility
Random access
Sequential access

60. HOW COMPUTERS WORK ?
A general purpose computer has four main sections;
• The arithmetic and logic unit (ALU)
• The control unit
• The memory
• The input and output devices (collectively termed I/O)
These parts are interconnected by busses

61. HOW COMPUTERS WORK ?

62. Control unit
Control Unit directs the various
components of a computer. It reads
and interprets (decodes)
instructions in the program one by
one. The control system decodes
each instruction and turns it into a
series of control signals that operate
the other parts of the computer.

63. Arithmetic/logic unit (ALU)
The ALU is capable of
performing two classes of
operations:
arithmetic and logic

64. Memory
A computer memory can
be viewed as a list of
cells into which numbers
can be placed or read

65. Input/ Output (I/O)
An input device converts incoming data and
instructions into a pattern of electrical signals
in binary code that are comprehensible to
a digital computer. An output device reverses
the process, translating the digitized signals into
a form intelligible to the user.

66. COMPUTER SOFTWARE
An invisible driver of Hardware
or a program, which allows the
hardware components to operate
effectively as well as provide
very many useful services.

67. Categories of Software
SOFTWARE
SYSTEM SOFTWARE
OPERATING
SYSTEM
SYSTEM
SERVICES
LANGUAGE
PROCESSOR
UTILITY
PROGRAMS
G.U.I
USER APPLICATION SOFTWARE
USER
PROGRAMS
COMMERCIAL
APPLICATION
PACKAGES
SPECIAL
PURPOSE
GENERAL
PURPOSE

68. System Software
The programs that protect the user
from the enormous complexity of
the computer system, and enable
the computer to be used to
maximum effect by a wide variety
of people, many of whom will
know very little about the inner
workings of computers.

69. Operating systems
Operating system acts as a
buffer between the user
and the complexities of the
computer itself

70. Main functions of operating systems
• Interpretation of the command language
• Error handling
• Protection of data files and programs
• Security
• Accounting
• Program Loading
• Multiprogramming
• Interrupt handling
• Job Sequencing
• File Management
• Job Scheduling
• Peripheral Control
• Recovery from System Failure

71. Types of Operating System
• Single Program OS
• Simple Batch Systems
• Multi-access and Time-sharing
• Real-time system

72. System Services
• Language Translators (Processors)
• Assembler
• Compiler
• Interpreter

73. Utility Programs
• Editors
• Debugging Aids
• File managers

74. Graphical User Interfaces (GUls)

75. USER APPLICATIONS SOFTWARE
programs for
which the
computer system
was specifically
purchased

76. User Programs
Programs written by people within
the organization for specific needs,
which cannot be satisfied by other
sources of software

77. Commercial Packages
kind of application packages
that are produced by software
professionals and be sold for a
wide variety of users

78. Special-purpose packages
Though commercial, it
is designed for a
specific purpose like a
department or a section
of an organization
• Airline Seat Reservation,
• Theatre Seat Reservation
• Hotel Room Reservation
• Point of Sales Software
• A Payroll Program

79. General Purpose
These provide facilities which
might be used in a wide variety
of business situation and which
might therefore be used across
many department of business
• Word-processing
• Database Management
• Spreadsheet
• Desktop Publishing &
Graphics Programs
• Communication Software

80. ADVANTAGES OF CUSTOM APPLICATION SOFTWARE (USER PROGRAMS)
• The needs of the organization are precisely met
• The method of inputting/outputting data may be designed to suit
user’s taste.
• It may require less memory and less disk space.
• Program may execute faster
• Programs can be changed to meet changing conditions.

81. DISADVANTAGES OF CUSTOM APPLICATION SOFTWARE
• Development time may be lengthy
• Human resources needed for development may not be available
• High cost of development (since it is designed for only one organization).
• Cost of maintenance / upgrading may be high

82. ADVANTAGES OF GENERIC APPLICATION SOFTWARE (COMMERCIAL APPLICATION PACKAGES)
• Availability is immediate as only installation process is necessary
before it can start being productive.
• Cost is less as it is spread among a number of users who purchase
the product.
• Reliability may be greater as it is thoroughly tested before it is
marketed.

83. DISADVANTAGES OF GENERIC APPLICATION SOFTWARE (COMMERCIAL APPLICATION PACKAGES)
• It may not be an exact match for needs
• It may require more system resources. Programs are frequently
longer, thereby, requiring more memory and disk space
• It is not adapted to changing needs
• It may execute more slowly.

84. GUIDELINE FOR ACQUISITION OF APPLICATION SOFTWARE
• The software to be acquired must be one whose use will improve the particular operating
function of that business.
• It must be of high performance
• The software to be acquired must be one with enough ease in learning.
• The software to be acquired must be available when needed
• If a software package is complex then training is required
• Good documentation: The package to be used must be properly documented. This should
include how the package is to be installed how to use the package and other necessary
technical details.
• Users friendliness: The package must be easy to use even by non- computer specialists.
• Compatibility of the package: Before a package program can be adopted, it must be
compatible with the user system requirements as well as with the user’s hardware.

85. SOCIAL IMPLICATION OF COMPUTERS ON THE SOCIETY
• The Office
• Manufacturing Industry
• Health
• Finance and Commerce
• Military Institution
• Education and Training
• Leisure

86. COMPUTER AS AN AID TO LAWYER
Computers are used in many law chambers to
record cases and courts proceedings

87. DATA PROCESSING TECHNIQUE
• Batch Processing
• On-line Processing
• Real-time processing
• Time Sharing
• Distributed Processing
• Centralized System
• Multitasking
• Multiprocessing

88. DATA COMMUNICATION AND NETWORKS
Movement of computer
information from one point to
another by means of electrical,
wireless or optical transmission
system

89. Communication Media
Device that transmits the voice
or the data form one point to
another
Guided
(Wired)
Radiated
(Wireless)

90. Data Transmission and Communication Devices
Data transmission refers to the
movement of data in form of bits
between two or more digital devices.

91. Data Transmission
Asynchronous
Transmit only one character at a
time
Synchronous
Data is sent as a block using
frames or packets

92. Data Transmission
ON-LINE DATA TRANSMISSION
Communication lines are directly
connected to the computer either
by means of a multiplexor or
(Transmission controller)or by
means of interface unit.
OFF-LINE DATA TRANSMISSION
Communication lines are not
connected directly to the
computer.

93. ELEMENTS OF DATA COMMUNICATION
• Information Source
• Message
• Transmitter
• Signal
• Receiver
• Information Destination

94. EQUIPMENT/COMPONENTS REQUIRED FOR DATA TRANSMISSION
• Multiplexor
• Front-End-Processor
• Concentrator
• Modem

95. TYPES OF TRANSMISSION
• Simplex Channel
• Half-Duplex
• Full- Duplex

96. COMPUTER NETWORKS
• An interconnected set of two
or more computers may be
called a "Computer Network".
A computer that is not
connected to other computers
is a "Stand-alone system".

97. Advantages of Using Computer Networks
• The sharing of resources (e.g. computers and staff) and information.
• The provision of local facilities without the loss of central control
• The even distribution of work
• Improved communication facilities

98. CATEGORIES OF NETWORKS
• Local Area Network (LAN)
• Metropolitan Area Network
(MAN)
• Wide Area Network (WAN)

99. COMPONENTS OF NETWORK
• Server or host computer
• Client
• Circuit

100. NETWORK TOPOLOGIES

101. INTERNET BASICS
Internet is an international
network of networks of
computers linking different
types of users: Academic,
Industries, Government, Health
Institutions, military, individuals,
etc, for the purpose of sharing
information

102. BENEFITS OF INTERNET APPLICATION
• Downloading of information
• Advertisement
• Accessing newspapers, magazines and academic journals
• On-line banking
• Accessing international media (CNN, BBC, VOA)

103. USES OF THE INTERNET
• Electronic Mail (E-MAIL)
• World Wide Web (WWW)
• TELNET
• File Transfer Protocol (FTP)
• USENET
• Gopher