INFORMATION
AND
COMMUNICATION
TECHNOLOGY
1
,TABLE OF CONTENTS
TABLE OF CONTENTS ................................................................................. 2
INFORMATION COMMUNICATION TECHNOLOGY ........................... 4
DEFINITION OF TERMS ........................................................................................................... 4
A BRIEF COMPUTER HISTORY .............................................................................................. 5
ADVANTAGES OF USING COMPUTERS ............................................................................... 8
CLASSIFICATION OF COMPUTERS ....................................................................................... 9
ROLE OF ICT IN A BUSINESS ENVIRONMENT .................................................................. 11
POSITIVE USE OF ICT IN THE SOCIETY ............................................................................. 12
NEGATIVE EFFECTS OF ICT IN THE SOCIETY .............................................................................. 13
COMPUTER HARDWARE .......................................................................... 15
HARDWARE CATEGORIES (FUNCTIONAL PARTS) ................................................................ 16
1. INPUT DEVICES ....................................................................................................... 16
2. PROCESSING DEVICES .......................................................................................... 25
3. OUTPUT DEVICES ................................................................................................... 28
4. STORAGE DEVICES AND MEDIA.................................................................................... 34
5. COMMUNICATION DEVICES .......................................................................................... 45
TYPES OF COMPUTER CABLES ........................................................................................... 45
SERIAL AND PARALLEL TRANSMISSION ........................................... 49
PARALLEL TRANSMISSION .......................................................................................................... 49
SERIAL TRANSMISSION ............................................................................................................... 49
COMPUTER HARDWARE SELECTION CRITERIA............................................................ 50
COMPUTER SOFTWARE – INTRODUCTION ....................................... 52
SYSTEM SOFTWARE.............................................................................................................. 52
APPLICATION SOFTWARE ................................................................................................... 56
CHOOSING APPROPRIATE COMPUTER SOFTWARE ....................................................... 58
BASIC COMPUTER NETWORKING ........................................................ 59
ADVANTAGES OF COMPUTER NETWORKING ................................................................ 59
TYPES OF NETWORKS........................................................................................................... 60
NETWORK COMPONENTS .................................................................................................... 63
NETWORK TOPOLOGIES ...................................................................................................... 72
INTERNET AND WORLD WIDE WEB .................................................................................. 78
ELECTRONIC MAIL (E-MAIL) .............................................................................................. 85
DATA PROCESSING .................................................................................... 97
DATA PROCESSING CYCLE ................................................................................................. 97
DATA PROCESSING MODES................................................................................................. 99
ELEMENTS OF DATA HIERARCHY ..................................................................................... 99
FILE ORGANIZATION AND ACCESS METHODS ............................................................. 100
DATA SECURITY........................................................................................ 103
THREATS AND HAZARDS TO DATA ................................................................................. 103
METHODS OF SECURING DATA ........................................................................................ 103
HARDWARE SAFETY ........................................................................................................... 106
SOFTWARE SAFETY ............................................................................................................ 107
COMPUTER CRIMES/CYBER CRIME ..................................................................................... 109
COMPUTER SAFETY AND ERGONOMICS.......................................... 120
ERGONOMICS ....................................................................................................................... 120
COMPUTER CARE & MAINTENANCE ............................................................................... 123
2
,ETHICS AND PROFESSIONAL ISSUES IN ICT ................................... 125
UNETHICAL BEHAVIOUR IN ICT ...................................................................................... 125
MEASURES TO FIGHT UNETHICAL USE OF ICT ............................................................. 126
SOURCES OF ICT LEGISTLATIONS ................................................................................... 126
DATA PROTECTION ACT ........................................................................................................... 127
CONFLICT MANAGEMENT .................................................................... 128
IMPORTANCE OF CONFLICT MANAGEMENT ................................................................ 128
CAUSES OF CONFLICT ........................................................................................................ 128
METHODS OF DEALING WITH CONFLICTS .................................................................... 129
TECHNIQUES OF STIMULATE CONFLICTS ..................................................................... 130
SOCIAL RESPONSIBILITY IN ICT......................................................... 131
ENVIRONMENTAL PROTECTION ..................................................................................... 131
KEYS TO SUCCESSFUL EFFORTS ...................................................................................... 131
CHALLENGES OF SOCIAL RESPONSIBILITY IN ICT ...................................................... 131
EMERGING TRENDS AND ISSUES IN ICT........................................... 132
1. E-LEARNING...................................................................................................................... 132
2. E-COMMERCE ................................................................................................................... 132
3. DOMESTIC APPLICATIONS OF ICT ............................................................................... 133
4. E-GOVERNMENT .............................................................................................................. 134
5. E-HEALTH .......................................................................................................................... 134
6. E-EMPLOYMENT .............................................................................................................. 134
7. E-ENVIRONMENT ............................................................................................................. 135
8. E-AGRICULTURE .............................................................................................................. 135
EMERGING ISSUES IN ICT .................................................................................................. 135
9. TECHNOLOGY TRANSFER ............................................................................................. 135
3
, INFORMATION COMMUNICATION TECHNOLOGY
DEFINITION OF TERMS
i) Computer
A computer is an electronic device that accepts and processes data into information and under the
control of instructions stored in its own memory and output or store the results for future use.
NB: An electronic device is a device that depends on the principles of electronics and uses the manipulation
of electron flow for its operation.
ii) Data
Data are raw, unprocessed and unorganized (unstructured) facts and figures that are relatively
meaningless to the user. E.g. number of hours worked by an employee.
iii) Information
Information is derived from data. This is data that is processed, organized/structured and
presented in a given context so as to make it useful. e.g., multiplying the hours worked by the
hourly rate to get each employee’s gross earning. Information is an important component in
decision making.
For example from a students test scores, the following information can be derived:
a) Class' average score
b) Most improved student
c) Median Score etc.
USES OF INFORMATION
(a) Decision-making
When managers are ready to make choices (decisions) they need good, accurate and up-to-date
information. If they act without relevant information it could lead to disaster, and failure.
(b) Monitoring and control
Businesses will compare actual performance against its predicted (budgeted) performance. Then they
will act upon it.
iv) Information Communication Technology/Technologies (ICT)
ICT is an umbrella term that covers any software or hardware product that can store, retrieve,
manipulate, transmit or receive information electronically in a digital form. Examples include
personal computers, digital television, email, robots, radio, cellular phones and networking
hardware.
For our study, we are concerned with computer (hardware and software) and telecommunications
technology (data, image, and voice networks).
v) Information System (IS)
An Information System (IS) is a combination of hardware, software, personnel, data and
procedures that interact to support and improve day-to-day operations in an organization. These
elements of an Information System are also known as the components of an Information System.
4
AND
COMMUNICATION
TECHNOLOGY
1
,TABLE OF CONTENTS
TABLE OF CONTENTS ................................................................................. 2
INFORMATION COMMUNICATION TECHNOLOGY ........................... 4
DEFINITION OF TERMS ........................................................................................................... 4
A BRIEF COMPUTER HISTORY .............................................................................................. 5
ADVANTAGES OF USING COMPUTERS ............................................................................... 8
CLASSIFICATION OF COMPUTERS ....................................................................................... 9
ROLE OF ICT IN A BUSINESS ENVIRONMENT .................................................................. 11
POSITIVE USE OF ICT IN THE SOCIETY ............................................................................. 12
NEGATIVE EFFECTS OF ICT IN THE SOCIETY .............................................................................. 13
COMPUTER HARDWARE .......................................................................... 15
HARDWARE CATEGORIES (FUNCTIONAL PARTS) ................................................................ 16
1. INPUT DEVICES ....................................................................................................... 16
2. PROCESSING DEVICES .......................................................................................... 25
3. OUTPUT DEVICES ................................................................................................... 28
4. STORAGE DEVICES AND MEDIA.................................................................................... 34
5. COMMUNICATION DEVICES .......................................................................................... 45
TYPES OF COMPUTER CABLES ........................................................................................... 45
SERIAL AND PARALLEL TRANSMISSION ........................................... 49
PARALLEL TRANSMISSION .......................................................................................................... 49
SERIAL TRANSMISSION ............................................................................................................... 49
COMPUTER HARDWARE SELECTION CRITERIA............................................................ 50
COMPUTER SOFTWARE – INTRODUCTION ....................................... 52
SYSTEM SOFTWARE.............................................................................................................. 52
APPLICATION SOFTWARE ................................................................................................... 56
CHOOSING APPROPRIATE COMPUTER SOFTWARE ....................................................... 58
BASIC COMPUTER NETWORKING ........................................................ 59
ADVANTAGES OF COMPUTER NETWORKING ................................................................ 59
TYPES OF NETWORKS........................................................................................................... 60
NETWORK COMPONENTS .................................................................................................... 63
NETWORK TOPOLOGIES ...................................................................................................... 72
INTERNET AND WORLD WIDE WEB .................................................................................. 78
ELECTRONIC MAIL (E-MAIL) .............................................................................................. 85
DATA PROCESSING .................................................................................... 97
DATA PROCESSING CYCLE ................................................................................................. 97
DATA PROCESSING MODES................................................................................................. 99
ELEMENTS OF DATA HIERARCHY ..................................................................................... 99
FILE ORGANIZATION AND ACCESS METHODS ............................................................. 100
DATA SECURITY........................................................................................ 103
THREATS AND HAZARDS TO DATA ................................................................................. 103
METHODS OF SECURING DATA ........................................................................................ 103
HARDWARE SAFETY ........................................................................................................... 106
SOFTWARE SAFETY ............................................................................................................ 107
COMPUTER CRIMES/CYBER CRIME ..................................................................................... 109
COMPUTER SAFETY AND ERGONOMICS.......................................... 120
ERGONOMICS ....................................................................................................................... 120
COMPUTER CARE & MAINTENANCE ............................................................................... 123
2
,ETHICS AND PROFESSIONAL ISSUES IN ICT ................................... 125
UNETHICAL BEHAVIOUR IN ICT ...................................................................................... 125
MEASURES TO FIGHT UNETHICAL USE OF ICT ............................................................. 126
SOURCES OF ICT LEGISTLATIONS ................................................................................... 126
DATA PROTECTION ACT ........................................................................................................... 127
CONFLICT MANAGEMENT .................................................................... 128
IMPORTANCE OF CONFLICT MANAGEMENT ................................................................ 128
CAUSES OF CONFLICT ........................................................................................................ 128
METHODS OF DEALING WITH CONFLICTS .................................................................... 129
TECHNIQUES OF STIMULATE CONFLICTS ..................................................................... 130
SOCIAL RESPONSIBILITY IN ICT......................................................... 131
ENVIRONMENTAL PROTECTION ..................................................................................... 131
KEYS TO SUCCESSFUL EFFORTS ...................................................................................... 131
CHALLENGES OF SOCIAL RESPONSIBILITY IN ICT ...................................................... 131
EMERGING TRENDS AND ISSUES IN ICT........................................... 132
1. E-LEARNING...................................................................................................................... 132
2. E-COMMERCE ................................................................................................................... 132
3. DOMESTIC APPLICATIONS OF ICT ............................................................................... 133
4. E-GOVERNMENT .............................................................................................................. 134
5. E-HEALTH .......................................................................................................................... 134
6. E-EMPLOYMENT .............................................................................................................. 134
7. E-ENVIRONMENT ............................................................................................................. 135
8. E-AGRICULTURE .............................................................................................................. 135
EMERGING ISSUES IN ICT .................................................................................................. 135
9. TECHNOLOGY TRANSFER ............................................................................................. 135
3
, INFORMATION COMMUNICATION TECHNOLOGY
DEFINITION OF TERMS
i) Computer
A computer is an electronic device that accepts and processes data into information and under the
control of instructions stored in its own memory and output or store the results for future use.
NB: An electronic device is a device that depends on the principles of electronics and uses the manipulation
of electron flow for its operation.
ii) Data
Data are raw, unprocessed and unorganized (unstructured) facts and figures that are relatively
meaningless to the user. E.g. number of hours worked by an employee.
iii) Information
Information is derived from data. This is data that is processed, organized/structured and
presented in a given context so as to make it useful. e.g., multiplying the hours worked by the
hourly rate to get each employee’s gross earning. Information is an important component in
decision making.
For example from a students test scores, the following information can be derived:
a) Class' average score
b) Most improved student
c) Median Score etc.
USES OF INFORMATION
(a) Decision-making
When managers are ready to make choices (decisions) they need good, accurate and up-to-date
information. If they act without relevant information it could lead to disaster, and failure.
(b) Monitoring and control
Businesses will compare actual performance against its predicted (budgeted) performance. Then they
will act upon it.
iv) Information Communication Technology/Technologies (ICT)
ICT is an umbrella term that covers any software or hardware product that can store, retrieve,
manipulate, transmit or receive information electronically in a digital form. Examples include
personal computers, digital television, email, robots, radio, cellular phones and networking
hardware.
For our study, we are concerned with computer (hardware and software) and telecommunications
technology (data, image, and voice networks).
v) Information System (IS)
An Information System (IS) is a combination of hardware, software, personnel, data and
procedures that interact to support and improve day-to-day operations in an organization. These
elements of an Information System are also known as the components of an Information System.
4
