JBD Computer Studies Book 9

Mouse

Mouse is a pointing device that is used in software
that supports graphical user interface such as
Windows operating systems. It gives input by
selecting and moving objects on the computer
screen. It executes commands by clicking on
icons, options and menus. The movement of
mouse controls the movement of the pointer on
the screen.

Trackball

Trackball is a cursor control device that is used
in many portable computers. It contains a ball
which can be rotated in any direction. The user
rolls the ball to direct the cursor to the desired
place on the screen and clicks any of the two
buttons near the trackball to select objects on the
desktop or position the cursor for text entry. It is
normally used in laptop computers.

Touch Sensitive Pad

Touch sensitive pad (track pad) is a stationary
pointing device that provides a small flat surface.
The user moves a stylus (or a finger) across a
flat surface to move the cursor on the screen.
It is commonly found in laptop computers.
Touchpads vary in size but are rarely made
larger than 40 square cm (about 6 square inches).

Touch Screen

Touch screen is a monitor that has a touch-
sensitive panel on the screen. The screens are
sensitive to pressure. It responds to the touches
of users by detecting the exact location of the
users’ fingers on the screen. Touchscreen has
three main components: a touch sensor, a
controller, and a software driver. It is widely used
on ATM machines, retail point-of-sale terminals,
car navigation systems, medical monitors and
industrial control panels.

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Joystick

Joystick is an input device consisting of a stick that
pivots on a base and reports its angle or direction
to the device it is controlling. It is often used to
control video games. It is also used for controlling
machines such as cranes, trucks, underwater
unmanned vehicles and zero turning radius lawn
mowers. Miniature finger-operated joysticks
have been adopted as input devices for smaller
electronic equipment such as mobile phones. A
popular variation of the joystick used on modern
video game consoles is the analog stick. The name
“joystick” is thought to originate with early 20th
century French pilot Robert Esnault-Pelterie.

Light Pen

Light pen is a light-sensitive input device shaped
like a pen, used to draw on the computer screen or
to make menu selection. It has a light sensor fixed
at the end of a pen-shaped tube and is capable of
sensing a position on the screen when its tip touches
the screen. It is used in applications where desktop
space is limited such as in the health-care field or
when a wide variety of people use the application,
such as electronic voting.

Scanner

Scanner is a device that captures images from
photographic prints, posters, magazine pages, and
similar sources for computer editing and display.
Scanners come in hand-held, feed-in, and flatbed
types and for scanning black-and-white only or
colour. Very high resolution scanners are used for
scanning for high-resolution printing, but lower
resolution scanners are adequate for capturing
images for computer display. Scanners usually
come with software, such as Adobe’s Photoshop
product, that lets you resize and otherwise modify
a captured image.

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Barcode Reader

Barcode reader, also called a price scanner or
point-of-sale ( POS ) scanner, is a hand-held or
stationary input device used to capture and read
information contained in a bar code. Barcode
reader consists of a scanner, a decoder (either
built-in or external), and a cable used to connect
the reader with a computer. Barcode reader
works by directing a beam of light across the
bar code and measuring the amount of light
that is reflected back. The scanner converts
the light energy into electrical energy, which
is then converted into data by the decoder and
forwarded to a computer. It is widely used in
supermarkets, libraries and retail stores.

3D scanner

3D scanner is a device that analyzes a real-
world object or environment to collect data on
its shape and possibly its appearance (i.e. color).
The collected data can then be used to construct
digital, three dimensional models useful for
a wide variety of applications. These devices
are used extensively by the entertainment
industry in the production of movies and
video games. Other common applications
of this technology include industrial design,
orthotics and prosthetics, reverse engineering
and prototyping, quality control/inspection and
documentation of cultural artifacts.

Web Camera

Web camera is a video capturing device that is
used to capture still images and videos. These
images can be stored in the computer, printed
or uploaded on the World Wide Web. It is used
for video conferencing where people placed
anywhere on the globe can hold a conversation
over the Internet.

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Output Devices
Output is the action of getting information from the computer. Once the CPU
has executed the program instruction, the program may ask that information
be communicated to an output device. The output device translates the data
processed in the computer from machine coded form into a human intelligible
form.
Outputs can exist in two forms:

Soft Copy Output
A soft copy is an electronic copy of some type of data, such as a file viewed on a
computer’s display or transmitted as an e-mail attachment. The most commonly
used soft copy output device on most personal computer system is a monitor.

Monitor
Monitor is a television like device connected to a computer that allows users to
view the result of processing. Modern computer monitors can display a wide
variety of information, including text, graphics, video and animation. The basic
types of monitors are cathode ray tube (CRT) monitors, liquid crystal display
(LCD) monitors and plasma monitors. The CRT monitors look like televisions, and
are used with non-portable computer systems. LCD monitors are flat and occupy
less space. Plasma monitors are mainly used for very large screens.

Hard Copy Output
A hard copy is a printed copy of information from a computer. Sometimes referred
to as a printout, a hard copy is so-called because it exists as a physical object. The
principal hard copy output devices are printers and plotters.

Printer
Printer is the most popular output device that produces output in a permanent
readable form. Computer printers are commonly divided into two general classes
according to the way they produce images on paper:
• Impact printer
• Non-impact printer

Impact Printer
Impact printer uses the electromechanical mechanism, that is physically striking
the hammers to strike a character against an inked ribbon. Each hammer is
embossed with the shape of an alphanumeric character and is transferred
through the inked ribbon onto the paper, resulting in a printed character. They
are relatively slow, noisy and inexpensive.

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i. Dot-matrix printer
Dot-matrix printer is an impact printer that works by using a ‘head’ to hammer

a ribbon or film coated with black carbon on a sheet of paper to form a pattern
of dots. It is cheaper and can print multiple copies simultaneously. It is good,
reliable workhorses ideal for use in situations where printed content is more
important than quality. It creates noise when the pins or typeface strike the
ribbon to the paper.

ii. Chain Printer
Chain printer consists of a set of slugs

mounted on a chain which rotates
horizontally in front of the paper. The
chain, containing letters, rotates at a
rapid speed. Hammers are present in
each print position like drum printer.
It strikes as soon as the appropriate
character appears in front of its print
position.

Non-impact Printer
Non-impact printer is that in which the printing is done with ink-jet, electrostatic,
chemical, laser beam and thermal technology. The quality of printing is very high.
It is less noisy, faster and produces high-quality graphics. Inkjet printer and laser
printer are examples of non-impact printers.

i. Laser printer
Laser printer is a high-speed, high quality non-impact printer that uses laser

beam to produce an image. A special ink called toner is attracted to the laser
exposed area of the drum. When the paper comes into contact with the drum,
the ink is fused on paper with heat and pressure. Laser printers are very
expensive and they produce high-quality output.

ii. Ink-jet printer
Ink-jet printer is a non-impact printer that uses print heads which have tiny

nozzles that spray out ink droplets onto the paper to form characters. These
nozzles can be heated very rapidly by an integrated circuit resistor. When the
resistor heats up, the ink near it vaporizes, and is ejected through the nozzle,
and makes a dot on the paper placed in front of the print head. Ink-jet printer
provides both high resolution and quiet operation. It is quiet and prints high
quality text and graphics.

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Graphic Plotter
Graphic plotter is a printer that interprets commands from a computer to make
line drawings on paper with one or more automated pens. Unlike a regular
printer, the plotter can draw continuous point-to-point lines directly from vector
graphics files or commands. There are a number of different types of plotters: a
drum plotter draws on paper wrapped around a drum which turns to produce
one direction of the plot, while the pens move to provide the other direction; a
flatbed plotter draws on paper placed on a flat surface; and an electrostatic plotter
draws on negatively charged paper with positively charged toner. They are most
frequently used for CAE (computer-aided engineering) applications, such as
CAD (computer-aided design) and CAM (computer-aided manufacturing).
Audio Output Devices
Audio output, which includes voice, music, and other sounds, is becoming
increasingly important in today’s world. Most desktop computers now include
speakers so that users can hear audio output. Voice output devices convert
digital data into sounds that human can understand as speech. Two basic types
of voice output devices are available. The first, more elementary method, stores
actual human voices speaking words in digital form and then reconverts them
into voice as needed. This method is limited to words previously stored in
the computer. The second type uses voice or speech synthesizers to artificially
generate sounds. They are being used to read out text information to blind person
and for translation systems.

Graphic Plotter

Audio Output Devices

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C Dompu- ictionary

BIOS : Acronym for basic input/output system, the boot
firmware program on a PC, and controls the computer
Cursor from the time you start it up until the operating system
CRT takes over.
Hard copy
Impact printer : A blinking point of light displayed on the screen to
help the user in the input of data.

: A screen whose pixels are coated with phosphorus,
causing them to glow when hit by an electron beam.

: Computer output in printed form.

: A type of printer that uses the electromechanical
mechanism, that is physically striking the hammers to
strike a character against an inked ribbon.

Recap

• The input/output (abbreviated I/O devices) provide the means of
communication between the computer.

• Input is the action of collecting raw-data at the beginning of a computer-based
information system into a form that is usable by the computer for processing.

• Mouse is a pointing device that is used in software that supports graphical
user interface such as Windows operating systems.

• Touch sensitive pad (track pad) is a stationary pointing device that provides
a small flat surface.

• Joystick is an input device consisting of a stick that pivots on a base and
reports its angle or direction to the device it is controlling.

• Light pen is a light-sensitive input device shaped like a pen, used to draw on
the computer screen or to make menu selection.

• Web camera is a video capturing device that is used to capture still images
and videos.

• Output is the action of getting information from the computer.

• A soft copy is an electronic copy of some type of data, such as a file viewed
on a computer’s display or transmitted as an e-mail attachment.

A hard copy is a printed copy of information from a computer.

• Impact printer uses the electromechanical mechanism, that is physically
striking the hammers to strike a character against an inked ribbon.

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Review Yourself

1. State whether the following statements are true or false.

a. A computer system can be useful, only when it is able to communicate
with its external environment (its users).

b. Keyboard is a pointing device that is used in software that support
graphical user interface such as Windows operating systems.

c. Touch sensitive pad (track pad) is a stationary pointing device that
provides a small flat surface.

d. A hardcopy is an electronic copy of some type of data, such as a file
viewed on a computer’s display or transmitted as an e-mail attachment.

e. Non-impact printer uses the electromechanical mechanism, that is
physically striking the hammers to strike a character against an inked
ribbon.

2. Match the following.

LCD A blinking point of light displayed on the screen to help
the user in the input of data.

CRT A software component that permits a computer system
to communicate with a device.

Cursor The act of entering data and instructions into a computer.

Input A screen whose pixels are coated with phosphorus,
causing them to glow when hit by an electron beam.

Device A type of display that uses a

Driver liquid compound having a polar molecular structure.

3. Fill in the blanks.

a. The ____________ devices establish the communication link between the
user and the computer system.

b. _____________ is a pointing device that is used in software that support
graphical user interface such as Windows operating systems.

c. ______________ is a light-sensitive input device shaped like a pen, used
to draw on the computer screen or to make menu selection.

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d. ____________ printer is an impact printer that works by using a ‘head’
to hammer a ribbon or film coated with black carbon on a sheet of paper
to form a pattern of dots.

e. ___________ printer is a high-speed, high quality non-impact printer
that uses laser beam to produce an image.

4. Give the appropriate technical term for the following.

a. The action of collecting raw-data at the beginning of a computer-based
information system into a form that is usable by the computer for
processing.

b. A stationary pointing device that provides a small flat surface.

c. A light-sensitive input device shaped like a pen used to draw on the
computer screen or to make menu selection.

d. A device that takes sound or speech as input and converts into a form
which can be stored in the computer memory.

e. An electronic copy of some type of data, such as a file viewed on a
computer’s display or transmitted as an e-mail attachment.

f. A type of a printer is that in which the printing is done with ink-jet,
electrostatic, chemical, laser beam and thermal technology.

5. Select the best answer from the list of choices.

a. The raw-data and program are entered into the computer through
__________.

i. Input devices ii. Output devices

iii. Computer memory iv. None of the above

b. ___________ is a monitor that has a touch-sensitive panel on the screen.

i. Trackball ii. Touch screen

iii. Joystick iv. All of the above

c. _____________ is a light-sensitive input device shaped like a pen, used
to draw on the computer screen or to make menu selection.

i. Mouse ii. Touchpad

iii. Light pen iv. None of the above

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d. _____________ uses the electromechanical mechanism, that is physically
striking the hammers to strike a character against an inked ribbon.

i. Non-Impact printer ii. Impact printer

iii. Plotter iv. All of the above

e. A printer that interprets commands from a computer to make line
drawings on paper with one or more automated pens.

i. Graphic plotter ii. Ink jet printer

iii. Laser printer iv. All of the above

6. Answer the following questions.
a. What is an input device? What are the functions of an input device?
b. What is a computer mouse? How does it differ from trackball?
c. What is touch sensitive pad?
d. What is a bar code reader, and how does it work?
e. What is a scanner? What are the different parts of a scanner?
f. What do you mean by output? Differentiate between soft copy output
and hard copy output?
g. Which device is called hard copy output device? List its types.
h. What is the difference between impact and non-impact printers?
i. What is graphic plotter? Where is it used?

7. Identify the following devices and name them.

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Chapter 6

SECONDARY
STORAGE

TECHNOLOGY

Objectives

After completing this chapter, you will be able to:
y Identify the different categories of secondary storage technology.
y Explain the different types of secondary storage media used to store data.
y Explain the differences between magnetic disk and optical disk.

C Ooncept verview

Secondary storage is an integral part of a computer’s peripheral equipment. It
is the memory that supplements the primary memory of a computer system. It
is long-term and non-volatile in nature. It facilitates the storage of large volume
of data on a more permanent basis for future reference. Information may be
erased from secondary media, but unlike primary storage, the information does
not disappear when the power supply to the machine is terminated. It can hold
much more data and is much less expensive than primary memory. However,
secondary storage is much slower than primary memory.
The two main types of secondary storage media (what data and programs
are actually stored on) are magnetic storage media and optical storage media.
Each type of media has a related secondary storage device that writes data
and instructions onto the storage media, reads what is on the media, and then
communicates it to the CPU. The two main factors to consider when looking at
different storage media and devices are the amount of data that can be stored and
the speed at which the data can be retrieved.

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Magnetic Tape

Magnetic tape is a medium for magnetic recording generally consisting of a thin
magnetizable coating on a long and narrow strip of plastic. It is usually 1/2 inch
or 1/4 inch wide and 50 to 2400 feet long. It has a very slow data access time and
access to information on magnetic tape is sequential, which means that to get to
a particular point on the tape, the tape must go through all the preceding points.
A device that stores computer data on magnetic tape can be called a tape drive, a
tape unit, or a streamer.

Advantages
• High data density
• Low cost and ease of handling

Disadvantages
• Lack of direct access to records
• Environmental problems-sensitive to dust, humidity and temperature levels

Magnetic Disk

Magnetic disk is a mylar or metallic platter that is covered with a magnetic coating
on which digital information is stored in the form
of microscopically small, magnetized needles. The
read/write head of magnetic disk helps to transfer
data. These heads are fastened to an arm in a disk
storage device so that they can be moved quickly
and directly to any disk location to store or retrieve
data. It offers high storage capacity, reliability, and
the capacity to directly access stored data. There are
two basic types of magnetic disks: floppy disk and
hard disk.

Hard Disk

Hard disk is a device used for mass storage of data that can be accessed directly.
It is capable of storing a large quantity of data. It is sealed inside a metal case to
prevent any foreign material from getting inside a container. Hard disk consists
of one or more platters. Each platter is a thin, circular metal plate coated on
both sides with a magnetic material. This platter is connected to a spindle. The
spindle rotates the disk platter at different speed between 3600 rpm (revolution
per minute) and 7200 rpm. Some new high-performance hard disks can spin as
fast as 10,000 rpm. There is an access arm having two read/write heads for each
recording surface of the platter to read/ write the data as the disk spins.

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Advantages
• Large storage capacity
• Stores and retrieve data much faste

Disadvantages
• Slower than RAM
• Disk is fixed inside the computer and is not portable

Floppy disk
The most common storage medium used in personal computer today is a floppy
disk. A floppy disk is made up of circular piece of thin plastic material with
magnetic coating on one or both the sides. This plastic disk is housed in a square
protective jacket or plastic shell to protect it against dust and scratches. Floppy
disk is inserted in a floppy disk drive unit which rotates the disk at approximately
300 revolution per minute inside its protective housing. The floppy disk drive
has a read/write head which accesses the magnetic surface to read data from it
or write information on it. Floppy disk contains a write-protected notch/slide,
which can be slide to protect it against being written on or to enable it to write.
The floppy disks are used to transfer small amounts of data between computers.
They are also used to hold back-up copies of the data and programs. A typical 3.5
inch floppy disk holds 1.44 MB of data.

Advantages
• Portable-small and light weight
• Inexpensive and reusable
• Useful for transferring data files between computers.

Disadvantages
• Not very strong-can be easily damaged
• Small storage capacity

Floppy Disk Capacities

Floppies can be found in different sizes with varying storage capacities. They
must be formatted before they can be used to store information. The amount
of data you can store on a diskette depends on the recording density and the
number of tracks on the diskette. Commonly used diskettes are referred to as
either double-density or high-density.

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Size (inches) 5.25 5.25 3.5 3.5

Type Double Density High Density Double Density High Density

Capacity 360K 1.2M 720K 1.44M
Tracks 40 80 80 80
Sectors/Track 9 15 9 18
Heads 2 2 2 2
Rotations/min 300 360 300 300
Data rate(kbps) 250 500 250 500
Bytes/sector 512 512 512 512

The disk capacity can be calculated by using the following formula:

Storage capacity = No. of bytes per sector x No. of sectors per track

x No. of tracks x No. of sides

1. Calculate the storage capacity of a 5.25” double sided double density disk.

Solution:

Storage capacity = No. of bytes per sector x No. of sectors per track x No. of tracks

x No. of sides

= 512 x 9 x 40 x 2

= 368640 bytes

= 360 KB

(i.e 1 KB = 1024 bytes)

2. Calculate the storage capacity of a 5.25” double sided high density disk.

Solution:

Storage capacity = No. of bytes per sector x No. of sectors per track x No. of tracks

x No. of sides

= 512 x 15 x 80 x 2

= 1228800 bytes

= 1228800/1024

= 1200 KB

= 1.2 MB



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3. Calculate the storage capacity of a 3.5” double sided double density disk.
Solution:

Storage capacity = No. of bytes per sector x No. of sectors per track x No. of tracks

x No. of sides

= 512 x 9 x 80 x 2

= 737280 bytes

= 737280/1024

= 720 KB

4. Calculate the storage capacity of a 3.5” double sided high density disk.
Solution:

Storage capacity = No. of bytes per sector x No. of sectors per track x No. of tracks

x No. of sides

= 512 x 18 x 80 x 2

= 1474560 bytes

= 1474560/1024

= 1440 KB

= 1.44 MB

Handling Floppy Disk

Floppy disks are vulnerable and easily damaged. Floppy disk should be taken
care as follows:

• Always keep the disk in its
envelope when you are not
using it.

• Never touch the surface of
the disk. Always hold a disk
by the label.

• Do not bend or crease the
disk.

• Always write the label
before sticking it onto the
disk.

• Keep disks away from dust
and liquids.

• Keep disks away from direct
heat.

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Zip Disk

Zip disk is a small portable disk. It is slightly larger
and twice as thick as normal floppies. It can typically
store 100 to 250 MB of data. Both the zip drive and
the zip disk are inexpensive and are used for backing
up the data on hard disks and also to transfer large
files between computers.

Super Disk

Super disk is a disk storage technology developed
by the Imation Corporation that supports very high-
density diskettes. Super disks are etched with a servo
pattern at the factory. This pattern is then read by the
Super Disk drive to precisely align the read/write head.
It can have 2,490 tracks per inch. Imation’s current
Super Disk drive is called the LS-120.

Optical Storage System

An optical disk is an electronic data storage medium that can be written to and
read using a low-powered laser beam. It provides tremendous storage capacities
at a relatively inexpensive price. It is most commonly used for storing music and
videos. The most commonly used optical storage medium are CD-ROM, CD-RW,
DVD, DVD-RW and Blue Ray disk.

Compact Disk-Read Only Memory

Compact disk (CD) is a small, portable,
round medium made of molded polymer for
electronically recording, storing, and playing
back audio, video, text, and other information
in digital form. It stores a large amount of data
through the use of laser optics technology.
The most common format of CD-ROM holds
approximately 650 megabyte of data. CD-ROMs
are faster, easier to handle and do not run the risk
of being destroyed by strong magnetic fields. On
the negative side, they are vulnerable to physical
damages such as scratches (especially on the
data surface). And though they are not affected
by strong magnetic field, they can be harmed by
high temperatures and strong light sources.

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Digital Versatile Disk-Read Only Memory

DVD-ROM is a high-density optical disk for storing
large amounts of data, especially high-resolution
audio-visual material. Like a CD drive, a DVD drive
uses a low-power laser to read digitized (binary)
data that have been encoded onto the disk in the
form of tiny pits. Because it uses a digital format, a
DVD can store any kind of data, including movies,
music, text and graphical images. DVDs are available
in single and double-sided versions, with one or two
layers of information per side. Single-sided DVDs
have become standard media for recorded motion
pictures, largely replacing videotape in the home
market. A double-sided, dual-layer version can store
about 30 times as much information as a standard
CD.

Digital Versatile Disk-Rewriteable

DVD-RW disk is a rewritable optical disk with equal storage capacity to a DVD-R,
typically 4.7 GB. The format was developed by Pioneer in November 1999 and
has been approved by the DVD forum. The smaller Mini DVD-RW holds 1.46
GB, with a diameter of 8 cm. The primary advantage of DVD-RW is the ability to
erase and rewrite to a DVD-RW disk. It is commonly used for volatile data, such
as backups or collections of files.

Blu-ray Disk

Blu-ray Disk (also called BD) is a high-density optical disk format for the storage of
digital media, including high-definition video. The name Blu-ray Disk is derived
from the blue-violet laser used to read and write this type of disk. A single layer
Blu-ray Disk can store 25 GB. A dual layer Blu-ray Disk can store 50 GB.

Pen Drive

Pen drive is a flash memory card that plugs into
the computer’s USB port. They are typically small,
lightweight, removable and rewritable. Pen drive
consists of a small printed circuit board encased in a
plastic or metal casing. The USB connector is usually
covered by a removable cap. The memory capacities
for USB pen drives currently are from 32 megabytes
up to 64 gigabytes.

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C Dompu- ictionary

CD-ROM : A rigid plastic disk that stores a large amount of data
through the use of laser optics technology.

DVD-ROM : An optical storage medium capable of storing
computer data and a full length movie on a single
disk.

Floppy disk : A circular piece of thin plastic material with magnetic
coating on one or both the sides.

Hard disk : A secondary storage medium, a magnetic disk that
usually resides permanently in the computer’s case
and can hold large amounts of data.

Magnetic disk : A metallic platter coated with a magnetic material on
which electronic data are stored.
Recap

• Secondary storage facilitates the storage of large volume of data on a more
permanent basis for future reference.

• Magnetic tape is a medium for magnetic recording generally consisting of a
thin magnetizable coating on a long and narrow strip of plastic.

• Magnetic disk is a mylar or metallic platter that is covered with a magnetic
coating on which digital information is stored in the form of microscopically
small, magnetized needles.

• Hard disk is a device used for mass storage of data that can be accessed directly.
It is capable of storing a large quantity of data.

• A floppy disk is made up of circular piece of thin plastic material with magnetic
coating on one or both the sides.

• Super disk is a disk storage technology developed by the Imation Corporation
that supports very high-density diskettes.

• An optical disk is an electronic data storage medium that can be written to and
read using a low-powered laser beam.

• Compact disk (CD) is a small, portable, round medium made of molded
polymer for electronically recording, storing, and playing back audio, video,
text, and other information in digital form.

• CD-RW (Compact Disk-Rewriteable) is a compact disk (CD) format that allows
repeated recording on a disk.

• Pen drive is a flash memory card that plugs into the computer’s USB port.

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Review Yourself

1. State whether the following statements are true or false.

a. Information may be erased from primary storage, but unlike secondary
media, the information does not disappear when the power supply to the
machine is terminated.

b. A device that stores computer data on magnetic tape can be called a tape
drive, a tape unit, or a streamer.

c. The spindle rotates the disk platter at different speed between 3600 rpm
(revolution per minute) and 7200 rpm.

d. A typical 3.5 inch floppy disk holds 600 MB of data.

e. Magnetic tape is a high-density optical disk for storing large amounts of
data, especially high-resolution audio-visual material.

f. An optical disk is an electronic data storage medium that can be written
to and read using a low-powered laser beam.

2. Fill in the blanks.

a. ____________ is usually 1/2 inch or 1/4 inch wide and 50 to 2400 feet long.

b. ____________ is sealed inside a metal case to prevent any foreign material
from getting inside, which causes head crash.

c. A ___________ is made up of circular piece of thin plastic material with
magnetic coating on one or both the sides.

d. ___________ is a disk storage technology developed by the Imation
Corporation that supports very high-density diskettes.

e. _____________ is a high-density optical disk for storing large amounts of
data, especially high-resolution audio-visual material.

3. Match the following. A secondary storage medium, a magnetic disk that
Laser usually resides permanently in the computer’s
case and can hold large amounts of data.
Track
Magnetic tape Secondary storage medium most commonly used
CD-ROM for backups.
Hard disk
A rigid plastic disk that stores a large amount of
data through the use of laser optics technology.

A device that produces and amplifies light.

An area used for storing data on a formatted disk.

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4. Give the appropriate technical term for the following.

a. A rigid plastic disk that stores a large amount of data through the use
of laser optics technology

b. A circular piece of thin plastic material with magnetic coating on one
or both the sides.

c. A secondary storage medium, a magnetic disk that usually resides
permanently in the computer’s case and can hold large amounts of
data.

d. A secondary storage medium most commonly used for backups.

e. A disk storage technology developed by the Imation Corporation that
supports very high-density diskettes.

f. An area used for storing data on a formatted disk.

5. Select the best answer from the list of choices.

a. A secondary storage that is usually 1/2 inch or 1/4 inch wide and 50 to
2400 feet long.

i. Magnetic disk ii. Magnetic tape iii. Optical disk

b. A secondary storage that is sealed inside a metal case to prevent any
foreign material from getting inside, which causes head crash.

i. Floppy disk ii. Zip disk iii. Hard disk

c. A typical 3.5 inch floppy disk holds ___________ MB of data.

i. 1.44 ii. 144 iii. 14.4

d. The storage capacity of a 5.25” double sided high density disk.

i. 1.2 MB ii. 320 MB iii. 1.44 MB

e. A disk storage technology developed by the Imation Corporation that
supports very high-density diskettes.

i. Zip disk ii. USB flash disk iii. Super disk

f. A very high-density information storage medium that uses light to
read and write digital information.

i. Optical disk ii. Magnetic tape iii. Magnetic disk

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6. Answer the following questions.
a. What is a secondary storage? What are the different types of secondary
storage medium?
b. What is a magnetic tape? Why is it called sequential access media?
c. State any two advantages and two disadvantages of magnetic tape.
d. What is a magnetic disk? Name two types of magnetic disks commonly
used in personal computers.
e. List any two advantages and disadvantages of hard disk.
f. Give a brief description of the floppy disk along with its diagram.
g. Calculate the storage capacity of a 5.25” double sided double density
disk.
h. What is a zip disk and a super disk?
i. What is an optical disk? How does it work?
j. Why is compact disk called ROM? What are the advantages of CD-
ROM?
k. What is a DVD-ROM? What is its typical capacity?

7. Identify the following devices and name them.

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Chapter 7

COMPUTER
SOFTWARE
CONCEPTS

Objectives

After completing this chapter, you will be able to:
y Define the term computer software and list the major types of computer software.
y Define system software and explain the different types of system software.
y List the important functions of an operating system.
y Define application software and explain the two major types of application

software.

C Ooncept verview

A computer cannot do anything on its own. It Operting Application
consists of hardware components which need System
instructions to solve a problem or execute a Application
task. Hence, it is necessary to specify a sequence User Application User
of instructions to carry out a specific task. Such User
sequence of instructions is called a program.
Software is the entire set of programs, procedures,
and routines associated with the operation of a
computer system, including the operating system.
It enables the hardware to operate; without them,
a computer cannot do anything at all. It would
just be a box of metal and plastic.

Computer software falls into two broad classes.
They are:

• System software

• Application software

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System Software
System software is the collection of programs designed to operate, control
and manage the actual operation of the computer equipment. It is like a layer
which acts as an interface between the computer and application software. It
helps the hardware components to work together, and provides support for
the development and execution of application software. Without the system
software, the computer cannot operate as a single unit. It includes combination
of the following:
• Operating System software
• Device driver
• Translating program
• Utility program

Operating System software
Operating system software is a master
control program that controls and
supervises a computer system’s hardware
and provides services to computer users.
It controls the flow of signals from CPU
to various parts of the computer. It acts
as a medium between the hardware and
the user or application software. The most
popular operating systems include MS-
DOS, Windows NT, Microsoft Windows,
Mac OS and Linux.
An operating system performs the following functions:
• To control and coordinate peripheral devices
• To monitor the use of the computer’s resources
• To help the application programs execute its instructions
• To help user develop programs
• To deal with any faults that may occur in the computer and inform the operator

Device driver
Device driver is a program that allows a hardware peripheral, such as a printer, to
communicate with a computer. Drivers are hardware-dependent and operating-
system-specific. DOS applications usually have their own proprietary device
drivers; under Windows all applications use the device drivers included with
Windows or provided by the hardware manufacturer for installation in Windows.

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Translating programs

Translating programs are part of the system software of the computer. It translates
the instructions written in human convenient form to machine language codes
understood by the computer. The translating programs are loaded into the
computer’s memory at the time of translation process. There is one translating
program for each programming language. There are three types of translating
programs. They are:

Assembly High Level
Language Code Language Code

Assembler Compiler/Interpreter

Machine Code

Assembler
Assembler is a computer program which translates the assembly language
programming into machine language program.

Compiler
Compiler is a computer program that translates a high level language program
into a machine language program at once. It reports all the errors of the program
along with the line numbers. Some of the programming languages such as C and
C++, use compilers.

Interpreter
Interpreter is a program that translates and executes a program written in a high
level language, line by line. If an error is found on any line, it is immediately
reported to the user and the execution of the program is stopped. The programming
language QBASIC normally uses an interpreter.

The major differences between compiler and interpreter are:
• Error correction is much simpler in the case of the interpreter because it is

done in stages. The compiler produces an error list for the entire program at
the end.
• Interpreters take more time for the execution of a program compared to
compilers because a statement has to be translated every time it is read.

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Utility program
Utility program is a program that ensures the smooth functioning of the computer.
It performs routine tasks, such as formatting disks, copying files from disk, sorting
files, and editing files, as well as other important housekeeping functions. Many
operating systems have utility programs built directly into the operating system
itself. Other utility programs are sold separately as software packages that the
user must install. A number of different kinds of utility programs are available. In
addition to disk utility routines already built into most operating systems, many
users add disk toolkits, data compression utilities, backup utility programs, virus
protectors and screen savers to their systems.

Application Software
Application software is a computer program designed to handle a particular task
required by the end-user. Application software can manipulate text, numbers,
graphics or a combination of these depending on the work for which it was
designed. Application software thus includes word processors, spreadsheets,
database management, inventory and payroll programs, and many other
“applications”. Application software may be written by a large software house
which distributes its products widely and addresses a general class of problems,
or may be written by an individual and addresses a particular problem.
There are two types of application software:
• Customized or Tailored software
• Packaged software

Customized or Tailored software
Customized or tailored software is the software designed to meet the specific
requirements of an organization or individual. Tailored software is written on the
demand of individual’s need and serves only a single organization. It is written in
high level languages such as Visual Basic and Visual C++. Some of the examples of
tailored software are payroll package, inventory package and library information
system.

Packaged software
Packaged software is a generalized set of programs that allows the computer
to perform a specific data processing job for the user. These programs are user
friendly and designed for use in more than one environment. Packaged software
may be purchased from software vendors.
Some of the most commonly used packaged software are Microsoft Word,
Microsoft Excel, Microsoft Access and Microsoft Frontpage.

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C Dompu- ictionary

Assembler : A built-in computer program which translates the
assembly language programming into machine
language program.

Application software: A program designed to handle a particular task
required by the end-user.

Compiler : A special program that translates a high level language
program into a machine code in a single operation.

Device driver : A program that allows a hardware peripheral, such as
a printer, to communicate with a computer.

Interpreter : A program that translates one statement of a high-level
language program into machine codes and executes it.

Object Program : A program which is obtained after being converted
into machine language.
Recap

• Software is the entire set of programs, procedures, and routines associated
with the operation of a computer system, including the operating system.

• Operating system software is a master control program that controls and
supervises a computer system’s hardware and provides services to computer
users.

• Device driver is a program that allows a hardware peripheral, such as a printer,
to communicate with a computer.

• Translating programs are part of the system software of the computer. It
translates the instructions written in human convenient form to machine
language codes understood by the computer.

• Assembler is a computer program which translates the assembly language
programming into machine language program.

• Compiler is a computer program that translates a high level language program
into a machine language program at once.

• Interpreter is a program that translates and executes a program written in a
high level language, line by line.

• Utility program is a program that ensures the smooth functioning of the
computer.

• Application software is a computer program designed to handle a particular
task required by the end-user.

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Review Yourself

1. State whether the following statements are true or false.

a. Software is the entire set of programs, procedures, and routines associated
with the operation of a computer system, including the operating system.

b. Without the system software, the computer operates as a single unit.

c. Compiler is a program that translates and executes a program written in
a high level language, line by line.

d. Tailored software is written on the demand of individual’s need and
serves only a single organization.

e. Wordprocessing software allows to communicate to any location in the
world using either fax or electronic mail.

2. Fill in the blanks.

a. _______________ software is a master control program that controls
and supervises a computer system’s hardware and provides services to
computer users.

b. ________________ is a program that allows a hardware peripheral, such
as a printer, to communicate with a computer.

c. ________________ translatesthe instructionswrittenin human convenient
form to machine language codes understood by the computer.

d. _______________ is a computer program that translates a high level
language program into a machine language program at once.

e. ________________ software is the software designed to meet the specific
requirements of an organization or individual.

3. Select the best answer from the list of choices..

a. A set of electronic instructions consisting of complex codes that makes
the computer perform tasks.

i. Hardware ii. Software

iii. Firmware iv. None of the above

b. A software that serves as an intermediary between hardware and
application software.

i. System software ii. Tailored software

iii. Application software iv. All of the above

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c. A computer program that allows other programs to interact with
computer hardware.

i. Operating system ii. Utility program

iii. Device driver iv. None of the above

d. A computer program that translates a high-level language program into
a machine code in a single operation.

i. Assembler ii. Compiler

iii. Interpreter iv. All of the above

e. A computer program designed to help the user in performing a certain
type of work.

i. Operating system ii. Utility program

iii. Application software iv. None of the above

4. Give the answer in one word.

a. A set of instructions written in computer language which instructs a
computer to perform a specified task.

b. A special program that translates a high level language program into a
machine code in a single operation.

c. The collection of programs designed to operate, control and manage the
actual operation of the computer equipment.

d. A program that allows a hardware peripheral, such as a printer, to
communicate with a computer.

e. A program that ensure the smooth functioning of the computer.
f. A computer program designed to handle a particular task required by

the end-user

5. Answer the following questions.
a. What do you understand by the term computer software?
b. What is a system software? Give an example of a system software.
c. What is an operating system? Why is it required?
d. What is a translating program? Name three translating programs.
e. What is an assembler?
f. What is a compiler? What are the differences between an interpreter and
a compiler?
g. What is utility program? Name any two utility programs.

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Chapter 8

COMPUTER
NUMBER
SYSTEM

Objectives

After completing this chapter, you will be able to:
y Define computer number system and explain the different types of computer

number system.
y Explain how to convert from one base system to another base system.
y Explain how to perform arithmetic operations on binary number system.
y Define the important terms related to storage system.

C Ooncept verview

Computer can serve as a tool to improve efficiency of any operation to be
performed. It is an electronic device. Data in a computer can be represented
by the presence or absence of electronic signals. In most computers, data is
represented as a group of binary digits: a combination of 0’s and 1’s. This is
known as representation of data. The number system used to represent data in a
computer is therefore known as binary number system.
Number system is an organized and systematic way of representing numbers.
The number system most familiar to us is decimal number system. This uses ten
digits (0,1,2,3,4,5,6,7,8,9) to represent numbers. However, other number systems
also exist-binary, octal and hexadecimal. These systems are used in operating
electronic devices.

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Decimal Number System
A system of numbers having base 10 is called decimal number system. It utilizes
the symbols of the numbers from 0 to 9. It is also called denary number system.
The value of decimal number is determined by
• the digit
• the position of the digit in the number
• the base or radix of the number system
For example, 758 is a decimal number.
758 = 7 x 102 + 5 x 101 + 8 x 100

= 7 x 100 + 5 x 10 + 8 x 1
= 700 + 50 + 8
= 758

Binary Number System
A system of numbers consisting of only two digits, 0 and 1 is called binary number
system. This is ideal for representing patterns of bits, with 0 expressing a bit that
is turned off and 1 expressing a bit that is turned on. It has base 2. The 0s and 1s
can be arranged in various combinations to represent all the numbers, letters and
symbols that can be entered into the computer.

Octal Number System
A system of numbers having base 8 is called octal number system. Octal number
system utilizes the digits from 0 to 7. The positional weights are based on
the powers of 8. The octal system is used in computing as a simple means of
expressing binary quantities.

Hexadecimal Number System
A system of numbers having base 16 is called hexadecimal number system. The
symbols used in this system are the decimal digits 0 through 9 and six additional
digits which are generally represented as A, B, C, D, E and F. The letters are used
because our standard numbering system has only 10 distinct digits in decimal
number system. The positional weights are based on the powers of 16.

Binary to Decimal Conversion
A binary number can be converted to its decimal equivalent by the following
method.
• Multiply each digit of binary number by base of the number (i.e. 2) raised to

the power of the positional notation taken from the extreme right.
• All the products of multiplication are added to get the decimal equivalent of

the number.

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Solved Examples

Convert the binary number (101010)2 to it decimal equivalent.
Solution:

Binary digits = 1 0 1 0 1 0

= 5 4 3 2 1 0
= (1x25)+( 0x24) + (1x23) + (0x22)+(1x21)+(0x20)

= (1x32) + (0x16) + (1x8) + (0x4) + (1x2) + (0x1)

= 32 + 0 + 8 + 0 + 2 + 0

= 4210
Thus, (101010)2 = (42)10
Decimal to Binary Conversion
A decimal number can be converted to its binary equivalent by the following
method.

• Divide the decimal number by 2 successively.

• Keep a note of the remainders in one column.

• Repeat the process until the quotient is zero.

• The answer is obtained by writing the answer in the reverse order.

Solved Examples

Convert the decimal number 2110 into binary equivalent.
Solution:

Remainders

2 21 1

2 10 0

2 5 1

2 2 0

2 1 1

0

Thus, (21)10 = (10101)2

Decimal to Octal Conversion
A decimal number can be converted to an octal by the following method:
• The number is divided by 8.
• The dividend is written under the number. This becomes the new number.

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• The remainder is noted at the right in a column.
• Steps first to third are repeated until a zero results.
• The octal number is read from the column of remainders from the bottom-up.

Solved Examples

Convert 411910 into octal.
Solution:
Remainders
8 4119 7
8 514 2
8 64 0
8 8 0
8 1 1
0
Thus, 411910 = 100278

Octal to Decimal Conversion
An octal number can be converted to its decimal equivalent by the following
method.
• The octal digits are written as powers of 8.
• Each power of 8 is converted into its decimal equivalent term.
• These terms are added to produce the required decimal number.

Solved Examples

Convert 6258 into decimal equivalent.
Solution:

Octal digits = 6 2 5

= 2 1 0

= (6x82)+(2x81)+(5x80)

= (6x64) + (2x8) + (5x1)

= 384 + 16 + 5

Thus, 6258 = 40510

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Octal to Binary Conversion
This is a straight forward method which instructs just to substitute the respective
values from the following table.
Octal Binary
0 000
1 001
2 010
3 011
4 100
5 101
6 110
7 111

Solved Examples

Convert 1058 to its binary equivalent.
Solution:
Octal digit = 1 0 5
From the table,
1 = 001
0 = 000
5 = 101
Thus, 1058 = 0010001012
Verification:
Octal digit = 1 0 5
= (1x82)+(0x81)+(5x80)
= 6910

Change 6910 into binary equivalent.
Remainders
2 69 1
2 34 0
2 17 1
2 8 0
2 4 0
2 2 0
2 1 1
0

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Now, put the binary digits in sets of three from the extreme right.
Binary number = 1 000 101
= (001) (000) (101)
Thus, 1058 = 0010001012

Binary to Octal Conversion

Binary to octal conversion is the reverse (inverse) process of octal to binary
conversion. The method is simple. Arrange the binary number into groups of
3 bits starting at the binary point and read each set of three binary digits using
table.

Solved Examples

Convert 11010102 into octal equivalent.
Solution:

Binary digits = 1101010

Paired binary no. = (001) (101) (010)

Now, locate the corresponding octal value of 001, 101 and 010 from the
table.

Octal value = (001) (101) (010)

Obtained = 1 5 2

Thus, (1101010)2 = (152)8

Verification:
Binary number = 1 1 0 1 0 1 0
= 6 5 4 3 2 1 0
= (1x26)+(1x25)+(0x24)+ (1x23) + (0x22) + (1x21) + (0x20)
= (1x64)+(1x32)+(0x16)+(1x8)+ (0x4)+(1x2)+(0x1)
= 64+32+0+8+0+2+0

= (106)10
Now, divide 10610 by base 8 to get the required result.
Remainder
8 106 2
8 13 5
8 1 1
0
Thus, 11010102 = 1528

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Decimal to Hexadecimal Conversion

A decimal number can be converted to the equivalent hexadecimal by the
following method:

• The decimal number is divided by 16.

• The dividend is written under the number. This becomes the new number.

• The remainder is noted at the right in a column. If the number is greater than
or equal to 10 then write its symbol.

• Step first to third are repeated till a ‘0’ is produced as the new number.

• The hexadecimal number is read from the column of remainders from the
bottom-up.
Solved Examples

Convert 8210 into hexadecimal equivalent.
Solution:
Remainders
16 82 2
16 5 5
0
Thus, 8210 = 5216

Hexadecimal to Decimal Conversion

A hexadecimal number can be converted to its decimal equivalent by the following
method.

• The hexadecimal digits of the given number are written as powers of 16.

• Each power of 8 is converted into its decimal equivalent term.

• These terms are added to produce the required decimal number.

Solved Examples

Convert B3E16 into decimal equivalent.
Solution:

Hexadecimal digits = B 3 E

= 2 1 0

= (Bx162) + (3x161) + (Ex160)

= (11x162) + (3x161) + (14x160)

= (11x256) + (3x16) + (14x1)

= 2816 + 48 + 14

= 287810
Thus, B3E16 = 287810

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Computer Studies-9

Binary to Hexadecimal Conversion

A binary number can be converted into hexadecimal number by the following
method:

• The given binary number is divided into groups of four bits each.

• Each group is replaced by its hexadecimal equivalent.

Solved Examples

Convert 1110112 into hexadecimal number system.
Solution:

Binary digits = 111011

Group the given binary number in sets of four. Make the sets equal by
adding two zeros to the extreme left. Replace each group by its hexadecimal
equivalent.

0011 1011

3 B

Thus, 1110112 = 3B10
Verification:

Binary number = 1 1 1 0 1 1

Positional notation = 5 4 3 2 1 0

Procedure = (1x22)+(1x22)+(1x22)+(0x22)+(1x22)+(1x22)

= (1x32)+(1x16)+(1x8)+(0x4)+ (1x2) + (1x1)

= 32 + 16 + 8 + 0 + 2 + 1

Answer = 5910

Now, divide 5910 by base 16 to get the required result.

Remainders

16 59 11=B

16 3 3

0

Answer = 3B

Thus, 1110112 = 3B16

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Hexadecimal to Binary Conversion
The hexadecimal number system is used as a shorthand method for representing
binary numbers in the same way as the octal number system. Each hexadecimal
digit is converted to its 4-bit binary equivalent.

Solved Examples

Convert 4A816 to its equivalent binary number.
Solution:
Hexadecimal number
4 A 8
0100 1010 1000

Thus, 4A810 = 0100101010002
Verification:

Hexadecimal number = 4 A 8

Positional notation = 2 1 0

Procedure = (4x162) + (10x161) + (8x160)

= (4x256) + (10x16) + (8x1)

= 1024 + 160 + 8

= 119210
Change 119210 into binary equivalent
Remainders

2 1192 0

2 596 0

2 298 0

2 149 1

2 74 0

2 37 1

2 18 0

2 9 1

2 4 0

2 2 0

2 1 1

0

Thus, 4A816 = 0100101010002

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Binary Arithmetic
Arithmetic operations (i.e. addition, subtraction, multiplication and division) in
binary number system are simple.
The binary addition rules are shown in the table below:

Solved Examples
Add 101110 with 100101.
Solution:
1 0 1 1 1 0 (Addend)
1 0 0 1 0 1 (Augend)
1 0 1 0 0 1 1 (Sum)
The binary subtraction rules are shown in the table below:

Solved Examples
Subtract 10110 from 11011.
Solution:
1 1 0 1 1 (Minuend)
1 0 1 1 0 (Subtrahend)
0 0 1 0 1 (Difference)

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The binary multiplication rules are shown in the table below:

Solved Examples

Multiply 1011 with 10001.

Solution:

1 0 1 1

x 1 0 0 0 1

1 0 1 1

0 0 0 0 x

0 0 0 0 x x

0 0 0 0 x x x

1 0 1 1 x x x x

1 0 1 1 1 0 1 1

The binary division rules are shown in the table below:

Solved Examples

Divide 11001 by 101.
Solution:
Starting from the most significant bit of dividend.
Step 1
Divisor Dividend Quotient
101 110011 1

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101 (Subtract)

1

Step 2

Divisor Dividend Quotient

101 110011 10

101

10

Step 3

Divisor Dividend Quotient

101 110011 101

101

101

101 (Subtract)

0
BITS, Nibble, Byte and Word

A single binary digit is called a bit. As a single bit carries so little information, we
usually group them together into chunks of eight bits called bytes. Half a byte
(four bits) is called a nibble.

Modern computers have registers and a data bus which are eight bits (or a
multiple) wide (for example 16, 32 or 64 bits). We refer to this as the word size of
a particular computer, and to this unit of information as a word.

Byte

Byte is a combination of 8 bits. A byte can represent a single character, such as
a letter, a digit, or a punctuation mark. Because a byte represents only a small
amount of information, amounts of computer memory and storage are usually
given in kilobytes, megabytes, gigabytes, terabytes and petabytes, exabytes,
zettabytes and yottabytes.

Kilobyte : A unit of computer memory or data storage capacity equal to
1,024 bytes.

Megabyte : A unit of computer memory or data storage capacity equal to
1,024 KB.

Gigabyte : A unit of computer memory or data storage capacity equal to
1,024 MB.

Terabyte : A unit of computer memory or data storage capacity equal to
1,024 GB.

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C Dompu- ictionary

Binary number system : A system of numbers consisting of only two digits, 0
and 1.

Nibble : A group of 4 bits.

Byte : A combination of 8 bits.

Kilobyte : A unit of computer memory or data storage capacity
equal to 1,024 bytes.

Megabyte : A unit of computer memory or data storage capacity
equal to 1,024 KB.

Gigabyte : A unit of computer memory or data storage capacity
equal to 1,024 MB.

Terabyte : A unit of computer memory or data storage capacity
equal to 1,024 GB.
Recap

• Computer can serve as a tool to improve efficiency of any operation to be
performed.

• The number system used to represent data in a computer is therefore known
as binary number system.

• A system of numbers consisting of only two digits, 0 and 1 is called binary
number system.

• A system of numbers having base 10 is called decimal number system.

• A system of numbers having base 8 is called octal number system.

• A system of numbers having base 16 is called hexadecimal number system.

• BIT is the smallest unit of information handled by a computer.

• Nibble is a group of 4 bits.

• Byte is a combination of 8 bits.

• Kilobyte (KB) is a unit of computer memory or data storage capacity equal to
1,024 bytes.

• Megabyte (MB) is a unit of computer memory or data storage capacity equal
to 1,024 KB.

• Gigabyte (GB) is a unit of computer memory or data storage capacity equal to
1,024 MB.

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Review Yourself

1. State whether the following statements are true or false.

a. A system of numbers consisting of only two digits, 0 and 1 is called
binary number system.

b. Byte is the smallest unit of information handled by a computer.
c. Kilobyte (KB) is a unit of computer memory or data storage capacity

equal to 1,024 bytes.
d. Exabyte is a unit of information or computer storage equal to 1,024 MB.
e. Zettabyte is a unit of information or computer storage equal to 1,024 EB.

2. Answer these questions.

a. What is a number system? What are the types of number systems used
in a computer?

b. What is a binary number system? What is the base of decimal number
system?

c. What is meant by byte in computer terminology? How many bytes are
there in 1011 1001 0110 1110 numbers?

d. A computer has 4KB words of main store. Each word comprises 24 bits.
How many bits are there in the whole memory?

3. Convert the following as indicated.

a. 110012 = (?)10 b. 11112 = (?)10
c 36210 = (?)2 d. 76410 = (?)2
e. 5710 = (?)8 f. 26010 = (?)8
g. 4378 = (?)10 h. 3218 = (?)10
i. 1012 = (?)8 j. 11102 = (?)8
k. 7268 = (?)2 l. 6158 = (?)2
m. 10710 = (?)16 n. 22010 = (?)16
o. 27D16 = (?)10 p. AB216 = (?)10
q. 110112 = (?)16 r. 101012 = (?)16
s. D8F916 = (?)2 t. 1AE16 = (?)2

4. Solve the following binary arithmetic. b. 101100 + 11101
a. 11011 + 10010 d. 111011 - 11011
c. 11111 - 1101 f. 110111 x 1001
e. 10111 x 11001 h. 111011 ÷ 111
g. 101111 ÷ 101

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Chapter 9

IT POLICY
OF NEPAL AND
E-GOVERNMENT

Objectives

After completing this chapter, you will be able to:
y Explain the importance of Information Technology.
y List the objectives of IT policy of Nepal.
y Define e-Government and explain the advantages and disadvantages of

e-Government.
y Explain the main domains of e-Government.
y Explain the types of e-Government services.

C Ooncept verview

Information Technology will be one of the key factors driving progress in the
21st century- it will transform the way we live, learn, work and play. Advances in
computing and communication technology will create a new infrastructure for
business, scientific research and social interaction. In most instances, information
technology has had a very positive impact, making our lives easier and more
productive. As the role of information technology in society has increased,
opportunities for crime have been created that never existed before. It can take
the form of money (e.g. the transfer of payments to the wrong accounts), the
theft of information (e.g. from files or databases), the theft of goods (by their
diversion to the wrong destination) or malicious vandalism (e.g. destruction of
data or introducing viruses).

Information technology is the use of computers and software to manage
information. In some companies, this is referred to as Management Information
Services (or MIS) or simply as Information Services (or IS). The information
technology department of a large company would be responsible for storing
information, protecting information, processing the information, transmitting
the information as necessary, and later retrieving information as necessary.

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Information Technology Policy of Nepal

Vision
“To place Nepal on the global map of information technology within the next five
years.”

Background
The world’s least developed countries including Nepal have availed themselves
of the opportunity to rapidly develop education, health, agriculture, tourism,
trade and various other sectors using information technology (IT). The extensive
application of this technology will engender economic consolidation, development
of democratic norms and values, proportional distribution of economic resources
and enhancement of public awareness, thereby raising living standards and
eventually contribute significantly to poverty alleviation. It is the information
technology, which will turn out to be a strong infrastructure for mitigating
Nepal’s geographical adversities.
In the coming years, globally, there will be a significant difference in the economic
conditions of the countries developed in the field of information technology and
of the countries lagging behind in this field. The persistence of such disparities
may not be congenial even for the developed countries.
In this context, there is a greater possibility that the international community
will extend its support to developing countries in the promotion of information
technology. Such assistance will certainly play a vital role in the national
development of a least developed country like Nepal. Hence, it has become
essential to formulate IT policy with a view to boosting up national economy.

Objectives
The information technology policy shall be formulated to achieve the following
objectives:
• To make information technology accessible to the general public and increase

employment through this means,
• To build a knowledge-based society, and
• To establish knowledge-based industries.

Strategies
The following information technology strategies shall be adopted to accomplish
the above-mentioned objectives through rapid development and extension of
information technology in a fair and competitive manner.

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• The government shall act as a promoter, facilitator and regulator.
• High priority shall be accorded to research, development and extension of

information technology with participation of private sectors.
• Competent manpower shall be developed with the participation of both the

public and the private sectors for the sustainable development and extension
of information technology.
• Domestic and foreign investment shall be encouraged for the development of
information technology and the related infrastructures.
• Nepal shall be placed on the global map of information technology.
• E-commerce shall be promoted with legal provisions.
• Information technology shall be used to assist e-governance.
• Information technology shall be applied for rural development.
• Information technology industry shall be promoted.
• Speedy and qualitative service shall be made available at a reasonable cost
by creating a healthy and competitive atmosphere among information
technology service providers.
• Computer education shall be incorporated in academic curriculum starting
from the school level.
• Professional efficiency shall be enhanced through the use of information
technology.
• Information technology network shall be extended to rural areas.
• Nepal shall be placed on the international market through information
technology.
• Export of services related to information technology (software and hardware)
shall be increased to 10 billion rupees within the next five years.

Information Technology Policy

The following policies shall be followed up for the implementation of the aforesaid
strategies:
• To declare information technology sector a priority sector,
• To adopt one window system for the development of information technology,
• To prioritize research and development in the field of information technology,
• To create an atmosphere conducive to attracting investment in the private

sector, keeping in view the private sector’s role in the development of
information technology,
• To provide Internet facilities gradually to all Village Development Committees
of the country,

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• To assist educational institutions and encourage domestic and foreign
training to fulfil the requirement of appropriate manpower at various levels
pertaining to information technology,

• To computerise the system in all government offices and build their websites
for the flow of information,

• To encourage the use of computers in private sectors,
• To develop physical and virtual information technology parks at various

places with private sector’s participation in the development of information
technology,
• To use information technology to promote e-commerce, e-ducation, e-health
among others, and to transfer technology to rural areas.
• To establish a National Information Technology Centre,
• To establish a fund at the national level by mobilizing resources from
Government of Nepal, donor agencies and private sectors so as to promote
research and development of information technology and other related
activities,
• To establish a venture capital fund with joint participation of public and
private sectors,
• To include computer education in the curriculum starting from the school
level and broaden its scope,
• To establish Nepal in the global market through the use of information
technology,
• To enact necessary laws for providing legal sanctions to the use of information
technology,
• To use information technology gradually in all government activities and
provide legal sanctions to them.

Action Plan

The following action plan shall be adopted to implement the national information
technology policy and fulfill its objectives:
• Participation of private sectors in infrastructure development
There may be up to cent percent foreign investment in areas such as

information technology park, research and development, technology transfer
and human resource development.

• Infrastructure development
The following arrangements shall be made for development of infrastructure

related to information technology

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a. An info-super highway and north-south info-highway shall be built taking
into account the rapidity of information flow, changes introduced through
information flow and the gradual development of multimedia service. Nepal
shall be linked with other parts of the world through a broadband information
network.

b. An IT park shall be established at Banepa in Kabhrepalanchok District. Such
IT Parks shall be established also elsewhere as required with private sector’s
participation.

c. Any company interested in establishing an industry within the park shall be
levied only 1% customs duty in importing IT related equipment for the next
five years.

d. Internet nodes shall be established in all development regions by fiscal year
2058/059 (2001/2002) and in district headquarters by fiscal year 2060/61
(2003/2004) with participation of the private sector in order to make Internet
facility available throughout the Kingdom. In making telephone contact with
such nodes, the telephone charge shall be levied on par with local calls; and
telephone contact with a nearby node within the development region shall be
deemed to be a local call, so long as the node in that district is not established.
The use of the Internet shall be gradually extended to rural areas as well.
The charge for telephone calls to be used for the Internet shall be gradually
reduced.

e. Telecommunications and electricity services shall be provided to the
entrepreneurs involved in information technology sector as per their need.

Human Resource Development

The following measures shall be adopted to develop skilled manpower:

a. Necessary facilities shall be provided to the universities in the country and
graduate and postgraduate-level classes of international standard shall be
offered in computer science and computer engineering subjects.

b. A long-term programme with a slogan “Computer education to all by 2010
A.D.” shall be formulated and computer education shall be offered as an
optional subject in some public secondary schools from the coming academic
year and shall be made a compulsory subject in phases.

c. IT shall be used to improve the quality of education.

d. Private sector shall be encouraged to prepare middle-level manpower required
for the information technology sector. Assistance shall be provided to the
private sector to set up institutions for education, research and development
in the field of information technology in each development region.

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e. Computer knowledge shall gradually be made compulsory to all newly-
recruited teachers so as to introduce computer education in schools; and
computer education shall also be provided to all in-service teachers in phases
using various means including distant education.

f. Emphasis shall be given to provide computer education from the school level.
Internet facility shall be made available free of cost to universities and public
schools for four hours a day within the next five years to provide computer
education in a systematic way.

g. Government of Nepal shall provide scholarships to public and private sector
technologists for higher study in information technology.

h. Necessary scholarships shall be provided to poor and meritorious students
from remote areas to pursue higher studies in information technology.

Dissemination of Information Technology

The following measures shall be followed up for the extensive dissemination of
information technology:

a. Educational institutions and hospitals in the areas where telecommunication
and electricity services are already available shall be encouraged to use IT
enabled services. Even in places where electricity service is not available, the
development of information technology through solar power system shall be
encouraged.

b. Distant learning system shall be introduced through the Internet and
Intranet apart from radio and television. Networking systems like school-net,
research-net, commerce-net and multilingual computing shall be developed.

c. A three-year programme shall be formulated and launched to extend the use
of computer in government offices. All ministries, departments and offices
shall be linked to the Internet; and other agencies shall also be encouraged to
be linked through the Internet.

d. Websites for all ministries, departments and district offices shall be created
within one year. Necessary legal provisions shall be made to reduce the use of
papers by using information technology in all kinds of government activities
in a phased manner.

e. An action plan shall be devised and introduced to include computer education
as a subject for the examination of a specified rank and make it obligatory for
the applicants taking a written examination during recruitment. Provisions
shall also be made for prescribing basic computer training as a requirement
for the promotion of employees.

f. Content shall be prepared to enhance Nepali materials on the Internet to
preserve Nepali arts and culture as well as to develop rural areas.

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g. A public awareness-enhancing campaign on the utility of information
technology shall be launched extensively through the electronic media.

h. Provision shall be made for an information officer in each ministry in a phased
manner.

i. In view of the present development of information technology, provisions
shall be made to open voice-mail to talk point-to-point for one’s own business
without a link to the public switched telephone network.

Promotion of E-commerce, etc.
E-business, tele-medicine, tele-processing, distant learning, and the like shall be
promoted as follows:
i. Necessary arrangements shall be made to encourage e-commerce.
ii. Necessary legal infrastructure shall be created for the promotion of tele-

medicine, distant learning, tele-processing and e-commerce.
iii. Intellectual property right shall be protected through the formulation of

necessary laws in relation to the development of information technology.
iv. Provisions shall be made for the export of software and IT enabled services

through IT in the following ways:
a. The person or organization concerned shall submit certified copies of the

documents on agreements relating to export to the Nepal Rastra Bank.
b. Invoice or bill of exportation made under the agreements referred to in clause

(a) shall be submitted to the Nepal Rastra Bank.
c. The Bank shall validate foreign currency earned on the basis of such

documents.

Facilities
The following facilities shall be provided for the development of information
technology sector:
a. One percent (1%) customs duty shall be levied on hardware, software and

all kinds of computer spare parts imported by training institutions related
to information technology, albeit on the recommendation of the National
Information Technology Centre on the basis of services rendered and the
achievements of such institutions.
b. As software development and services based on software are operated twenty-
four hours, such services shall be declared essential services to guarantee
regular production by employees working in the companies related to such
services, and arrangements shall be made accordingly.
c. A venture capital fund shall be established by utilizing capital market with
the joint investment of His Majesty’s Government and private sector. His
Majesty’s Government shall make an investment of 100 million rupees
initially for such a fund.

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d. Domestic preference shall be given in accordance with the prevailing law on
computers, spare parts and software produced within the country.

e. Software may be directly depreciated for the purposes of income tax, whereas
equipment relating to information technology may be allowed an accelerated
depreciation in two years.

f. In case an investment has been made in foreign currency either as a loan or
share capital required to build and operate infrastructure, the investor shall
be allowed to repatriate the principal amount and interest of the loan and
dividends in accordance with the prevailing laws.

g. The foreign currency earned from exporting information technology software
and services shall be granted facilities on par with facilities provided to other
export-oriented industries earning foreign currency.

h. An information technology development fund shall be established to create
public awareness about information technology, assist rural networking,
develop information technology with market management, generate
required manpower for this sector and make social services easily accessible
where such technology is used. Arrangements shall be made for financial
contributions towards this fund from His Majesty’s Government, private
sector, donor agencies and others. The National Information Technology
Centre (NITC) shall operate this fund. A feasibility study shall be carried
out to mobilise additional financial resources by establishing information
technology bond.

i. Export of software shall be subjected to an additional service charge of 0.5
% for the information technology fund, in addition to customs duties. The
amount obtained from that charge shall be deposited in the fund referred to
in clause 6.6.8.

j. As Nepali nationals working abroad can play an important role in technology
transfer and market promotion in this sector, they shall be encouraged to
invest their foreign currency earnings in this sector.

Concept of E-Government
E-government is a general term describing the use of technologies to facilitate the
operation of government and the disbursement of government information and
services. E-government is an abbreviation of the phrase electronic government.
E-government deals heavily with Internet applications to aid in governments,
but also covers a number of non-Internet concerns.
E-government can serve a variety of different ends: better delivery of government
services to citizens, improved interactions with business and industry, citizen
empowerment through access to information, or more efficient government
management. The resulting benefits can be less corruption, increased transparency,
greater convenience, revenue growth, and/or cost reductions.

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