Chapter 1
Information Communication Technology and You
Objectives:
 To differentiate between ICT and information system
 To describe the components of an information system
 To examine the four types of computer: The mainframe, minicomputer, supercomputer
and the personal computer
 To illustrate the hardware devices used for input, processing, storage, output and
communications
 To describe some common storage devices
 To give an introduction on computer connectivity, the Internet and the Web
Learning Outcomes:
At the end of this chapter, the students will be able to:
1. Appreciate the differentiate between ICT and information system
2. Describe the five main components of an information system
3. Describe the difference between the mainframe, minicomputer, supercomputer and the
personal computers
4. Explain the features of the hardware devices used for input, processing, storage, output
and communications
5. Explain the features of some common storage devices
6. Understand how computers can be connected to a network, Internet and the Web
1.1 The five parts of an information system: people, procedures, software, hardware and data
Information and Communications Technology - or technologies (ICT) is an umbrella term that
includes all technologies for the manipulation and communication of information. The term is
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sometimes used in preference to Information Technology (IT), particularly in two communities:
education and government. Although, in the common usage it is often assumed that ICT is
synonymous with IT; it encompasses:

any medium to record information (magnetic disk/tape, optical disks (CD/DVD), flash
memory etc. and arguably also paper records);

technology for broadcasting information - radio, television; and

technology for communicating through voice and sound or images - microphone,
camera, loudspeaker, telephone to cellular phones.
It includes the wide variety of computing hardware (PCs, servers, mainframes, networked
storage), the rapidly developing personal hardware market comprising mobile phones, personal
devices, MP3 players, and much more; the full gamut of application software from the smallest
home-developed spreadsheet to the largest enterprise packages and online software services;
and the hardware and software needed to operate networks for transmission of information,
again ranging from a home network to the largest global private networks operated by major
commercial enterprises and, of course, the Internet. Thus, "ICT" makes more explicit that
technologies such as broadcasting and wireless mobile telecommunications are included.
Information System
The term "information system" or IS has different meanings. It sometimes refers to a system of
persons, data records and activities that process the data and information in an organization,
and it includes the organization's manual and automated processes. Computer-based
information systems are the field of study for information technology, elements of which are
sometimes called an "information system" as well, a usage some consider to be incorrect. In
organizational informatics an information system is a system of communication between
people. Information systems are systems involved in the gathering, processing, distribution and
use of information and as such support human activity systems. The most common view of an
information system is one of Input-Process-Output.
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Components of Information System
A computer-based information system (CBIS) is an information system in which the computer
plays a major role. Figure 1 describes how the components of an information system are
related to each other. Such a system consists of the following elements:
People
Every CBIS needs people if it is to be useful. Often the most over-looked element of the CBIS is
the people: probably the components that most influence the success or failure of information
system. There are many roles for people in information systems. Common ones include

Systems Analyst

Programmer

Technician

Engineer

Network Manager

MIS (Manager of Information Systems)

Data entry operator
Procedures
Procedures are the policies that govern the operation of a computer system. "Procedures are to
people what software is to hardware" is a common analogy that is used to illustrate the role of
procedures in a CBIS. A procedure is a series of documented actions taken to achieve
something. A procedure is more than a single simple task. A procedure can be quite complex
and involved, such as performing a backup, shutting down a system, patching software.
Hardware
When you think "equipment", immediately think "Hardware AND Software" The term hardware
refers to machinery. This category includes the computer itself, which is often referred to as the
central processing unit (CPU), and all of its support equipments. Among the support
equipments are input and output devices, storage devices and communications devices.
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Software
The term software refers to computer programs and the manuals (if any) that support them.
Computer programs are machine-readable instructions that direct the circuitry within the
hardware parts of the CBIS to function in ways that produce useful information from data.
Programs are generally stored on some input / output medium-often a disk or tape.
Data
Data are facts that are used by program to produce useful information. Like programs, data are
generally stored in machine-readable from on disk or tape until the computer needs them. The
raw, unorganized, discrete (separate, isolated) potentially-useful facts and figures that are later
processed (manipulated) to produce information.
People
Data
Hardware
Software
Procedures
Figure 1: Components of an Information System
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1.2
Four kinds of computers – microcomputer, minicomputer, mainframe, and
supercomputer
Four Kinds of Computers
Computers are categorized on the basis of physical structures and the purpose of their use.
Based on capacity, speed and reliability they can be divided into four categories of computers:
The Mainframe Computer – These are computers used by large organizations like
meteorological surveys and statistical institutes for performing bulk mathematical
computations. They are core computers which are used for desktop functions of over one
hundred people simultaneously. A mainframe (also known as "big iron") is a high-performance
computer used for large-scale computing purposes that require greater availability and security
than a smaller-scale machine can offer. Historically, mainframes have been associated with
centralized rather than distributed computing, although that distinction is blurring as smaller
computers become more powerful and mainframes become more multi-purpose. The
mainframe is sometimes referred to as a "dinosaur" not only because of its size but because of
reports, going back many years, that it's becoming extinct. In the early years of computing, the
original mainframes were housed in room-sized metal frames, which is probably where the
name derives from. In the past, a typical mainframe might have occupied 2,000 - 10,000 square
feet. Newer mainframes are about the same size as a large refrigerator.
The Microcomputer – These are the most frequently used computers better known by the
name of “Personal computers”. This is the type of computer meant for public use. Other than
Desktop Computer the choice ranges as follows:

Personal Digital Computer

Tablet PC

Towers

Work Stations

Laptops
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
Hand Held Computer
A microcomputer is a complete computer on a smaller scale and is generally a synonym for the
more common term, personal computer or PC, a computer designed for an individual. A
microcomputer contains a microprocessor (a central processing unit on a microchip), memory
in the form of read-only memory and random access memory, I/O ports and a bus or system of
interconnecting wires, housed in a unit that is usually called a motherboard.
The Mini computer – Mini computers like the mainframe computers are used by business
organization. The difference being that it can support the simultaneous working of up to 100
users and is usually maintained in business organizations for the maintenance of accounts and
finances. A minicomputer, a term no longer much used, is a computer of a size intermediate
between a microcomputer and a mainframe. Typically, minicomputers have been stand-alone
computers (computer systems with attached terminals and other devices) sold to small and
mid-size businesses for general business applications and to large enterprises for departmentlevel operations.
The Super Computer - It is somewhat similar to mainframe computers and is used in economic
forecasts and engineering designs. Today life without computers is inconceivable. Usage of
different types of computers has made life both smooth and fast paced. A supercomputer is a
computer that performs at or near the currently highest operational rate for computers. A
supercomputer is typically used for scientific and engineering applications that must handle
very large databases or do a great amount of computation (or both).
Hardware devices for input, processing, storage, output and communications
Input Devices
An input device is any hardware component that allows you to enter data, programs,
commands and user responses into a computer. Some popular include keyboard, mouse,
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trackballs, and light pens, digital camera, scanner, and microphone. Table 1 summarizes a list of
input, output and devices that are commonly used.
Keyboard
This is the most common input device for home and commercial users. It is made up of a set of
typewriter-like keys that enables you to enter data into a computer. Computer keyboards are
similar to electric-typewriter keyboards but contain additional keys. The keys on computer
keyboards are often classified as follows:

Alphanumeric keys -- letters and numbers

Punctuation keys -- comma, period, semicolon, and so on.

Special keys -- function keys, control keys, arrow keys, Caps Lock key, and so on.
The standard layout of letters, numbers, and punctuation is known as a QWERTY keyboard
because the first six keys on the top row of letters spell QWERTY.
Output Devices
It refers to any machine capable of representing information from a computer. This includes
display screens, printers, plotters, and synthesizers. Refer to Table 1 for a complete list.
a) Display screen - The display part of a monitor. Most display screens work under the same
principle as a television, using a cathode ray tube (CRT). Consequently, the term CRT is often
used in place of display screen. Abbreviation of cathode-ray tube, the technology used in most
televisions and computer display screens. A CRT works by moving an electron beam back and
forth across the back of the screen. Each time the beam makes a pass across the screen, it lights
up phosphor dots on the inside of the glass tube, thereby illuminating the active portions of the
screen. By drawing many such lines from the top to the bottom of the screen, it creates an
entire screen-full of images.
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b) Printer
Dot-Matrix Printer - a set of steel pins strike an inked ribbon onto paper producing any desired
sequence of dots.
Ink-Jet Printer - fires a jet of liquid ink through tiny holes and it gives high resolution for almost
professional quality, sharp printing.
Laser Printer - works like a photocopier, powdered ink is fused onto paper by heat and
pressure. The sharpness of the print is considered to be of very high resolution and suitable if
we require full professional printing quality.
Table 1: Typical Computer Input/output and Storage Devices
Input
Output
Storage
Keyboard
Monitor
Floppy Disk
Mouse
Printers (all types)
Diskette
Trackballs
Audio Card
Hard Disk
Touchpads
Plotters
Disk Cartridge
Pointing Sticks
LCD Projection
Panels
CD-ROM
Joysticks
Computer Output
Microfilm (COM)
Optical Disk
Pen Input
Facsimile (FAX)
Magnetic Tape
Touch Screen
Speaker(s)
Cartridge Tape
Light Pen
.
Reel Tape
Digitizer
.
PC Card
Graphics Tablet
.
RAID
Scanner
.
Memory Button
Microphone
.
Smart Card
Electronic
Whiteboard
.
Optical Memory
Card
Video Cards
.
USB memory stick.
Audio Cards
.
.
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Some Common Storage Devices
Hard Drive
The hard drive is the primary device that a computer uses to store information. The hard drive
stores programs, data files, saves files, and organizes files. The hard drive is located inside the
computer case. The hard drive, magnetically stores data on stacks of rotating disks called
platters.
Floppy Drive
The floppy drive stores and retrieves information on a floppy disk.
CD -ROM Drive
CD-ROM is a device that reads information stored on a compact disc. CD-ROM stands for
Compact Disc Read Only Memory. One CD is equal to the space in over 40 floppy disc.
Removable Hard Disk
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A zip disk is a removable disk that holds a large amount of information. A zip disk can be used to
achieve, protect and transfer large amounts of data.
Zip Drive & Zip Disk
RAID -- Redundant Array of Inexpensive Disks
As users get more and more sophisticated, they develop applications; such as multimedia
systems, that requires large memory size and fault tolerance to be built into the storage device.
This is where the RAID technology comes in. The RAID technology is an affordable alternative to
mass storage with a high throughput and reliability.
A RAID is simply and array of small disks together to obtain the performance of more expensive
high end disks. It is based on the idea that disk throughput can be increased by having many
disk drives with many heads operating in parallel. The distribution of data over multiple disks
automatically forces access to several disks at one time improving throughput. Disk arrays can
be used to store large amounts of data, have high I/O rates and take less power per megabyte
(when compared to high end disks) due to their size.
Optical Storage
Optical storage has been the most popular storage medium in the multimedia context due its
compact size, high density recording, easy handling and low cost per MB. CD is the most
common, while Laser disc and DVD are also popular.
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DVD
DVD, which stands for Digital Video Disc, Digital Versatile Disc, is the next generation of optical
disc storage technology. DVD has become a major new medium for a whole host of multimedia
system. It's essentially a bigger, faster CD that can hold video as well as audio and computer
data. DVD aims to encompass home entertainment, computers, and business information with
a single digital format, eventually replacing audio CD, videotape, laserdisc, CD-ROM, and
perhaps even video game cartridges. DVD has widespread support from all major electronics
companies, all major computer hardware companies, and most major movie and music studios.
Communication devices
When we use computers, we usually need to transfer data and information from one computer
to another. The transmission of data from one location to another is done digitally, meaning
that the data are translated into bits of ‘0’s and ‘1’s. Connectivity refers to the use of computer
networks to link to people and resources. You can link or connect to large computers and the
Internet providing access to world-wide information resources just by sitting in front of and
clicking on your computer. On a larger, collective scale connectivity may refer to the internet
bandwidth coming into and going out of a country, and the quality of the infrastructure within
the country for linking to the internet.
To connect a computer to a network we need to use communication devices. These devices
include: modem, network interface card, wireless network interface card, network access point
transmitter and
Modem, short for modulator-demodulator is an electronic device that converts a computer’s
digital signals into specific frequencies to travel over telephone or cable television lines. At the
destination, the receiving modem demodulates the frequencies back into digital data.
Computers use modems to communicate with one another over a network.
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A network interface card, more commonly referred to as a NIC, is a device that allows
computers to be joined together in a LAN, or local area network. Networked computers
communicate with each other using a given protocol or agreed-upon language for transmitting
data packets between the different machines, known as nodes. The network interface card acts
as the liaison for the machine to both send and receive data on the LAN. The most common
language or protocol for LANs is Ethernet. An Ethernet network interface card is installed in an
available slot inside the computer. A network interface card does not have to be hard wired
with physical cable. Wireless network interface card, such as the Wireless Ethernet cards are
installed like their wired counterparts, but rather than a port for an Ethernet cable, the card
features a small antenna. The card communicates with the central wireless switch or hub via
radio waves. Wireless Internet access, sometimes referred to as a “hot spot,” is a local area
network (LAN) run by radio waves rather than wires. Wireless Internet access is broadcast from
the central hub which is a hard-wired device that actually brings in the Internet connection. The
hub, located at the main computer system or server, broadcasts Internet connectivity to clients,
which is basically anyone within “hearing” range who is equipped with a wireless LAN card.
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1.3
Computer connectivity, the Internet and the Web
Expansion capabilities of a computer: slots, cards and bus
Most of computer components lay on a card of switch-plates called motherboard. However, we
could need to connect other devices to motherboard in order that they can interact with
processor and other components. That is realized through inserting an expansion card in one of
I/O connectors of the motherboard.
An expansion card, when inserted, fits perpendicularly in a connector of the motherboard and
has to be fixed by a screw on the opposite side. When computer is closed, we can be sure that
the expansion card will remain well connected to the motherboard. Cards communicate each
other and with other computer components through the so-called bus representing an internal
computer network through which signals are transmitted from/to any computer part.
Therefore, because of this connection system, any card inserted in a computer slot can
communicate with other computer components, memory and microprocessor included. These
slots, conceivable as bus connectors, offer a simple way for adding further equipment. In the
original PC, bus used just 8-bit cards and could transfer about one million byte per second. As of
now, a motherboard with a Pentium processor has a 32 PCI bit bus allowing transfer of 500
million byte per second. Obviously, a Pentium processor mounted on an 8-bit motherboard
could not exploit most of its capacities. During the last years many types of bus have been
designed, with different performances. Compatibility between buses and current cards is a
critical topic.
Communication ports
External peripherals are connected to a computer through cables (or radio or infrared rays)
using connectors called communication ports. There are many types, but the main ports are
two: parallel and serial.
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Parallel ports
Parallel ports or interfaces are so called because data transmitted between peripheral devices
and central unit are sent byte by byte: the 8 bit of each byte are therefore sent in parallel (8 bit
a time). Parallel ports are mainly used for connecting printer: for this reason every computer is
equipped with a parallel port. There can be many parallel ports for connecting simultaneously a
printer, a scanner, a backup device or a copy protection key (dongle).
Serial ports
Differently from parallel ones, serial ports do not transmit 8 bit a time, in parallel, but send bit
by bit; i.e. one bit a time. Therefore 8 bit of a byte are sequentially sent, at a speed 8 times
slower at least than a speed reachable by a parallel method. Serial ports are however more
versatile and polyvalent, being used to connect PC to various types of peripherals, such as
mouse, scanner, modem, external units.
Internet
The Internet is a computer network made up of thousands of networks worldwide. There are
organizations which develop technical aspects of this network and set standards for creating
applications on it. All computers on the Internet communicate with one another using the
Transmission Control Protocol/Internet Protocol suite (TCP/IP). Computers on the Internet use
client/server architecture. This means that the remote server machine provides files and
services to the user's local client machine. Software can be installed on a client computer to
take advantage of the latest access technology.
An Internet user has access to a wide variety of services: electronic mail, file transfer, vast
information resources, interest group membership, interactive collaboration, multimedia
displays, real-time broadcasting, breaking news, shopping opportunities, and much more.
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World Wide Web
The World Wide Web (WWW) is a system of Internet servers that supports hypertext to access
several Internet protocols on a single interface. Almost every protocol type available on the
Internet is accessible on the Web. This includes e-mail, FTP, Telnet, and Usenet News. In
addition to these, the World Wide Web has its own protocol: HyperText Transfer Protocol, or
HTTP.
Summary:
Information and Communications Technology - or technologies (ICT) is an umbrella term that
includes all technologies for the manipulation and communication of information. ICT is not to
be confused with Information System (IS). Information systems are systems involved in the
gathering, processing, distribution and use of information and as such support human activity
systems. Components of IS are: people, hardware, software, data and procedures.
A mainframe is a high-performance computer used for large-scale computing purposes that
require greater availability and security than a smaller-scale machine can offer. A
microcomputer is a complete computer on a smaller scale and is designed for an individual.
Mini computers are used by business organization and they can support the simultaneous
working of up to 100 users and is usually maintained in business organizations for the
maintenance of accounts and finances. A supercomputer is typically used for scientific and
engineering applications that must handle very large databases or do a great amount of
computation (or both).
Hardware devices for input include keyboards and the mouse, scanner, touch screen and
joystick. Hardware for processing includes the CPU chip such as the Intel Pentium II. Storage
devices include the hard drive, CD, DVD, RAID, and optical disc. The output devices can be the
screen, the printer and the speaker. Communication devices include modem, network interface
cards, wireless network interface cards and network access point transceiver.
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External peripherals are connected to a computer through cables using connectors called
communication ports. Parallel ports are mainly used for connecting printer. Serial ports are
used to connect PC to various types of peripherals, such as mouse, scanner, modem, external
units.
The Internet is a computer network made up of thousands of networks worldwide. The World
Wide Web (WWW) is a system of Internet servers that supports hypertext to access several
Internet protocols on a single interface.
Quiz
No.
Question
1
The term ICT is synonymous to IT.
2
ICT includes technologies such as broadcasting and wireless mobile
telecommunications.
3
An information system is a system of communication between computer
systems.
4
A Network Manager is a component of an information system
5
A procedure can be quite complex and involved, such as performing a
backup, shutting down a system, patching software. It tells the computer
what to do.
6
A mainframe is a high-performance computer used for large-scale
computing purposes and are associated with distributed rather than
centralized computing
7
A microcomputer contains a microprocessor, memory, I/O ports and a bus,
all on the motherboard.
8
A minicomputer is a computer which is between a microcomputer and a
mainframe and is used by small businesses for general business applications
and to large enterprises for department-level operations.
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True/False
9
A supercomputer is typically used for e-commerce applications that must
handle very large response rate from customers around the world.
10
The touch screen is an example of input and output device.
11
A hardware device can function as both input and output device.
12
A storage device can outside the computer.
13
A storage device can be added on to the computer to cater for extra
memory requirement.
14
Communication devices are required to enable computers to send data and
information from one location to another.
15
External peripherals are connected to a computer through cables using
connectors called communication ports.
Answer:
1 = T, 2 = T, 3 = F, 4 = F, 5 = T, 6 = F, 7 = T, 8 = T, 9 = F, 10 = F, 11 = F, 12 = T, 13 = T, 14 = T, 15 = T
Essay questions:
1. Explain the difference between the terms ICT and information system.
2. Describe briefly the components of an information system. How are they related to each
other?
3. What are the types of computer?
4. Give an example of an application for each of the following computer:
a. Mainframe
b. Minicomputer
c. Supercomputer
d. personal computer
5. Give three examples of hardware devices used for:
a. Input
b. Processing
c. Storage
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d. Output
e. communications
6. Describe two common storage devices used by a mainframe, minicomputer, supercomputer
and the personal computer
7. Give a brief explanation of the following terms:
a. computer connectivity
b. Internet
c. Web
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