NCERT Textbook -Network Security, Information & Computer Technology Class 10 | Information & Computer Technology (Class 10) - Notes & Video PDF Download

 Page 1


109
Network Security
Chapter 6
Network Security
Learning Objectives 
By the end of this chapter, learner will be able to:
•	 Name	 the	 diff er en t	 kinds	 of	 softw ar e	 licensing	 a v ailable
•	 Diff er en tia t e	 be tw een	 fr ee w ar e	 and	 open	 sour ce	 softw ar e
•	 St a t e	 ho w	 the	 use	 of	 shar e w ar e	 softw ar e	 is	 diff er en t	 fr om	 tha t	 of	 fr ee w ar e	 softw ar e
•	 Diff er en tia t e	 be tw een	 c op yrigh t	 and	 licensing
•	 De fine	 cyber e thics,	 cyber sa f e ty	 and	 cyber security
•	 St a t e	 the	 purpose	 of	 c ookies
•	 T abula t e	 the	 diff er en t	 phases	 of	 cyber	 e thics	 e v olution
•	 Lis t	 pr ec autions	 tha t	 c an	 be	 t ak en	 t o	 ensur e	 cyber	 sa f e ty
•	 Iden tif y	 the	 diff er en t	 kinds	 of	 thr ea ts	 t o	 cyber	 security
•	 St a t e	 e thic al	 beha viour	 t o	 be	 f ollo w ed	 as	 a	 cyber	 citiz en
•	 Iden tif y	 the	 diff er en t	 c a t eg ories	 of	 cyber	 crime
IntroduCtIon
The world created by technology is one of machines - computers, computer systems and 
computer networks. Add to that the human component and one has a world of diverse 
cultures and social practices that is often referred to as cyberspace. 
Cyberspace is a man made world that is constantly evolving. It differs from the static 
physical world as it has no boundaries, no geographical mass, and of course, no gravity. It is 
limitless, constantly changing its shape, attributes and characteristics. It exists in a form of 
bits and bytes; it is an information driven world. Government(s), hardware manufacturers 
and software application providers act as gatekeepers of cyberspace. 
This medium, which is dynamic, infinite and intangible has to be regulated to prevent 
it from exploding. Regulating cyberspace means regulating both man and the machine. 
There is ethics, safety and security involved. 
Ethics represents personal choice. It’s the set of acceptable behaviours in a given culture. 
It’s not just a list of rules but the code of conduct by which a society chooses to live. Safety 
refers to safe practices and security is the additional tasks carried out to ensure safety. 
Page 2


109
Network Security
Chapter 6
Network Security
Learning Objectives 
By the end of this chapter, learner will be able to:
•	 Name	 the	 diff er en t	 kinds	 of	 softw ar e	 licensing	 a v ailable
•	 Diff er en tia t e	 be tw een	 fr ee w ar e	 and	 open	 sour ce	 softw ar e
•	 St a t e	 ho w	 the	 use	 of	 shar e w ar e	 softw ar e	 is	 diff er en t	 fr om	 tha t	 of	 fr ee w ar e	 softw ar e
•	 Diff er en tia t e	 be tw een	 c op yrigh t	 and	 licensing
•	 De fine	 cyber e thics,	 cyber sa f e ty	 and	 cyber security
•	 St a t e	 the	 purpose	 of	 c ookies
•	 T abula t e	 the	 diff er en t	 phases	 of	 cyber	 e thics	 e v olution
•	 Lis t	 pr ec autions	 tha t	 c an	 be	 t ak en	 t o	 ensur e	 cyber	 sa f e ty
•	 Iden tif y	 the	 diff er en t	 kinds	 of	 thr ea ts	 t o	 cyber	 security
•	 St a t e	 e thic al	 beha viour	 t o	 be	 f ollo w ed	 as	 a	 cyber	 citiz en
•	 Iden tif y	 the	 diff er en t	 c a t eg ories	 of	 cyber	 crime
IntroduCtIon
The world created by technology is one of machines - computers, computer systems and 
computer networks. Add to that the human component and one has a world of diverse 
cultures and social practices that is often referred to as cyberspace. 
Cyberspace is a man made world that is constantly evolving. It differs from the static 
physical world as it has no boundaries, no geographical mass, and of course, no gravity. It is 
limitless, constantly changing its shape, attributes and characteristics. It exists in a form of 
bits and bytes; it is an information driven world. Government(s), hardware manufacturers 
and software application providers act as gatekeepers of cyberspace. 
This medium, which is dynamic, infinite and intangible has to be regulated to prevent 
it from exploding. Regulating cyberspace means regulating both man and the machine. 
There is ethics, safety and security involved. 
Ethics represents personal choice. It’s the set of acceptable behaviours in a given culture. 
It’s not just a list of rules but the code of conduct by which a society chooses to live. Safety 
refers to safe practices and security is the additional tasks carried out to ensure safety. 
110
Information and Computer Technology
The first is a moral choice, the second a behavioural code and the third involves active 
participation.
in cyberspace we have 
 ? Cyberethics exploring appropriate and ethical behaviours related to online 
environments and digital media. It includes plagiarism, bullying, and hacking to 
name a few.
 ? Cybersafety defining how one operates on-line. It includes rules guiding how to keep 
personal information safe and limited
 ? Cybersecurity involving tasks undertaken on the computer to keep it secure from 
people who wish to harm it or use data stored on it unlawfully. This includes installing 
virus software and firewalls.
Before we study these in greater detail there are certain fundamental terminology and 
concepts that must be understood.
1. BaSIC terMInoloGy 
1.1 Copyright and license
Copyright is about protecting original expression. Copyright 
arises as soon as a ‘work’ is created. A software copyright 
protects all source code, written text materials, graphic 
images/ designs, drawings, any linked sound, video files 
or films.
A copyright owner has five exclusive rights: 
 ? Fix or store the information in a tangible form.
 ? Reproduce the copyrighted material. 
 ? Sell, rent, lease, or otherwise distribute copies of the copyright work to the public.
 ? Publicly perform and display the copyrighted material.
 ? Prepare derivative works based on the copyrighted material.
l icense is the permission granted by the holder of a copyright to another to use an 
original work. It states under what circumstances and to what extent the original work 
can be used, changed or distributed. It may include a period of time, a geographical area, 
renewal provisions, and other limitations. It does not pass on the copyright. 
Page 3


109
Network Security
Chapter 6
Network Security
Learning Objectives 
By the end of this chapter, learner will be able to:
•	 Name	 the	 diff er en t	 kinds	 of	 softw ar e	 licensing	 a v ailable
•	 Diff er en tia t e	 be tw een	 fr ee w ar e	 and	 open	 sour ce	 softw ar e
•	 St a t e	 ho w	 the	 use	 of	 shar e w ar e	 softw ar e	 is	 diff er en t	 fr om	 tha t	 of	 fr ee w ar e	 softw ar e
•	 Diff er en tia t e	 be tw een	 c op yrigh t	 and	 licensing
•	 De fine	 cyber e thics,	 cyber sa f e ty	 and	 cyber security
•	 St a t e	 the	 purpose	 of	 c ookies
•	 T abula t e	 the	 diff er en t	 phases	 of	 cyber	 e thics	 e v olution
•	 Lis t	 pr ec autions	 tha t	 c an	 be	 t ak en	 t o	 ensur e	 cyber	 sa f e ty
•	 Iden tif y	 the	 diff er en t	 kinds	 of	 thr ea ts	 t o	 cyber	 security
•	 St a t e	 e thic al	 beha viour	 t o	 be	 f ollo w ed	 as	 a	 cyber	 citiz en
•	 Iden tif y	 the	 diff er en t	 c a t eg ories	 of	 cyber	 crime
IntroduCtIon
The world created by technology is one of machines - computers, computer systems and 
computer networks. Add to that the human component and one has a world of diverse 
cultures and social practices that is often referred to as cyberspace. 
Cyberspace is a man made world that is constantly evolving. It differs from the static 
physical world as it has no boundaries, no geographical mass, and of course, no gravity. It is 
limitless, constantly changing its shape, attributes and characteristics. It exists in a form of 
bits and bytes; it is an information driven world. Government(s), hardware manufacturers 
and software application providers act as gatekeepers of cyberspace. 
This medium, which is dynamic, infinite and intangible has to be regulated to prevent 
it from exploding. Regulating cyberspace means regulating both man and the machine. 
There is ethics, safety and security involved. 
Ethics represents personal choice. It’s the set of acceptable behaviours in a given culture. 
It’s not just a list of rules but the code of conduct by which a society chooses to live. Safety 
refers to safe practices and security is the additional tasks carried out to ensure safety. 
110
Information and Computer Technology
The first is a moral choice, the second a behavioural code and the third involves active 
participation.
in cyberspace we have 
 ? Cyberethics exploring appropriate and ethical behaviours related to online 
environments and digital media. It includes plagiarism, bullying, and hacking to 
name a few.
 ? Cybersafety defining how one operates on-line. It includes rules guiding how to keep 
personal information safe and limited
 ? Cybersecurity involving tasks undertaken on the computer to keep it secure from 
people who wish to harm it or use data stored on it unlawfully. This includes installing 
virus software and firewalls.
Before we study these in greater detail there are certain fundamental terminology and 
concepts that must be understood.
1. BaSIC terMInoloGy 
1.1 Copyright and license
Copyright is about protecting original expression. Copyright 
arises as soon as a ‘work’ is created. A software copyright 
protects all source code, written text materials, graphic 
images/ designs, drawings, any linked sound, video files 
or films.
A copyright owner has five exclusive rights: 
 ? Fix or store the information in a tangible form.
 ? Reproduce the copyrighted material. 
 ? Sell, rent, lease, or otherwise distribute copies of the copyright work to the public.
 ? Publicly perform and display the copyrighted material.
 ? Prepare derivative works based on the copyrighted material.
l icense is the permission granted by the holder of a copyright to another to use an 
original work. It states under what circumstances and to what extent the original work 
can be used, changed or distributed. It may include a period of time, a geographical area, 
renewal provisions, and other limitations. It does not pass on the copyright. 
111
Network Security
1.2 Software licensing
A software license is a legal agreement about an 
application. It is between the software producer and 
the end-user and is an important part of the legally 
binding contract between them (or rights owner) 
and the end-user. This is to ensure recognition of the 
rights of the owner on his creation. It specifies how 
the application may be used and defines the rights of 
both the producer and the user. 
1.3 open Source, freeware and Shareware 
o pen-source software (OSS) is computer software with its source code made available. It is 
very often developed in a public, collaborative manner. A license for open sources software 
allows the end user to study, change and distribute the software for any purpose. 
Some copyrighted software is made available for use, free of charge for an unlimited time. 
These are called freeware. The copyright still remains with the producer / owner for any 
future development. 
s hareware are copyrighted software that can be shared for a limited on a trial basis with 
the understanding that if the user decides to use it, he will pay for it. 
1.4 t ypes of software licenses
 ? Proprietary license where the copyright stays with the producer and the user is 
granted the right to use the software
 ? gnu g eneral Public l icenses, which are agreements under which “open source” 
software is usually licensed. It allows end users to change the source code, but the 
changed code too, must also be made available under a GNU GPL license.
 ? e nd u ser l icense a greement (EULA) indicates the terms under which the end-
user may use the software.
 ? Workstation licenses are licenses that permit the installation of an application on 
a single computer. Before installing it on a different machine the software must be 
removed from the first machine
 ? Concurrent use licenses permit the installation of the software onto multiple 
machines as long as the number of computers using the software at the same time 
does not exceed the number of licenses purchased.
Page 4


109
Network Security
Chapter 6
Network Security
Learning Objectives 
By the end of this chapter, learner will be able to:
•	 Name	 the	 diff er en t	 kinds	 of	 softw ar e	 licensing	 a v ailable
•	 Diff er en tia t e	 be tw een	 fr ee w ar e	 and	 open	 sour ce	 softw ar e
•	 St a t e	 ho w	 the	 use	 of	 shar e w ar e	 softw ar e	 is	 diff er en t	 fr om	 tha t	 of	 fr ee w ar e	 softw ar e
•	 Diff er en tia t e	 be tw een	 c op yrigh t	 and	 licensing
•	 De fine	 cyber e thics,	 cyber sa f e ty	 and	 cyber security
•	 St a t e	 the	 purpose	 of	 c ookies
•	 T abula t e	 the	 diff er en t	 phases	 of	 cyber	 e thics	 e v olution
•	 Lis t	 pr ec autions	 tha t	 c an	 be	 t ak en	 t o	 ensur e	 cyber	 sa f e ty
•	 Iden tif y	 the	 diff er en t	 kinds	 of	 thr ea ts	 t o	 cyber	 security
•	 St a t e	 e thic al	 beha viour	 t o	 be	 f ollo w ed	 as	 a	 cyber	 citiz en
•	 Iden tif y	 the	 diff er en t	 c a t eg ories	 of	 cyber	 crime
IntroduCtIon
The world created by technology is one of machines - computers, computer systems and 
computer networks. Add to that the human component and one has a world of diverse 
cultures and social practices that is often referred to as cyberspace. 
Cyberspace is a man made world that is constantly evolving. It differs from the static 
physical world as it has no boundaries, no geographical mass, and of course, no gravity. It is 
limitless, constantly changing its shape, attributes and characteristics. It exists in a form of 
bits and bytes; it is an information driven world. Government(s), hardware manufacturers 
and software application providers act as gatekeepers of cyberspace. 
This medium, which is dynamic, infinite and intangible has to be regulated to prevent 
it from exploding. Regulating cyberspace means regulating both man and the machine. 
There is ethics, safety and security involved. 
Ethics represents personal choice. It’s the set of acceptable behaviours in a given culture. 
It’s not just a list of rules but the code of conduct by which a society chooses to live. Safety 
refers to safe practices and security is the additional tasks carried out to ensure safety. 
110
Information and Computer Technology
The first is a moral choice, the second a behavioural code and the third involves active 
participation.
in cyberspace we have 
 ? Cyberethics exploring appropriate and ethical behaviours related to online 
environments and digital media. It includes plagiarism, bullying, and hacking to 
name a few.
 ? Cybersafety defining how one operates on-line. It includes rules guiding how to keep 
personal information safe and limited
 ? Cybersecurity involving tasks undertaken on the computer to keep it secure from 
people who wish to harm it or use data stored on it unlawfully. This includes installing 
virus software and firewalls.
Before we study these in greater detail there are certain fundamental terminology and 
concepts that must be understood.
1. BaSIC terMInoloGy 
1.1 Copyright and license
Copyright is about protecting original expression. Copyright 
arises as soon as a ‘work’ is created. A software copyright 
protects all source code, written text materials, graphic 
images/ designs, drawings, any linked sound, video files 
or films.
A copyright owner has five exclusive rights: 
 ? Fix or store the information in a tangible form.
 ? Reproduce the copyrighted material. 
 ? Sell, rent, lease, or otherwise distribute copies of the copyright work to the public.
 ? Publicly perform and display the copyrighted material.
 ? Prepare derivative works based on the copyrighted material.
l icense is the permission granted by the holder of a copyright to another to use an 
original work. It states under what circumstances and to what extent the original work 
can be used, changed or distributed. It may include a period of time, a geographical area, 
renewal provisions, and other limitations. It does not pass on the copyright. 
111
Network Security
1.2 Software licensing
A software license is a legal agreement about an 
application. It is between the software producer and 
the end-user and is an important part of the legally 
binding contract between them (or rights owner) 
and the end-user. This is to ensure recognition of the 
rights of the owner on his creation. It specifies how 
the application may be used and defines the rights of 
both the producer and the user. 
1.3 open Source, freeware and Shareware 
o pen-source software (OSS) is computer software with its source code made available. It is 
very often developed in a public, collaborative manner. A license for open sources software 
allows the end user to study, change and distribute the software for any purpose. 
Some copyrighted software is made available for use, free of charge for an unlimited time. 
These are called freeware. The copyright still remains with the producer / owner for any 
future development. 
s hareware are copyrighted software that can be shared for a limited on a trial basis with 
the understanding that if the user decides to use it, he will pay for it. 
1.4 t ypes of software licenses
 ? Proprietary license where the copyright stays with the producer and the user is 
granted the right to use the software
 ? gnu g eneral Public l icenses, which are agreements under which “open source” 
software is usually licensed. It allows end users to change the source code, but the 
changed code too, must also be made available under a GNU GPL license.
 ? e nd u ser l icense a greement (EULA) indicates the terms under which the end-
user may use the software.
 ? Workstation licenses are licenses that permit the installation of an application on 
a single computer. Before installing it on a different machine the software must be 
removed from the first machine
 ? Concurrent use licenses permit the installation of the software onto multiple 
machines as long as the number of computers using the software at the same time 
does not exceed the number of licenses purchased.
112
Information and Computer Technology
 ? site licenses permit the use of software on any computer at a specified site. Unlimited 
site licenses allow the installation of the software on any number of computers as 
long as those computers are located at the specified site.
 ? Perpetual licenses come without an expiry date and allow the software to be used 
indefinitely
 ? n on-perpetual licenses “lease” the software for use for a specified period of time, 
usually annually or sometimes bi-annually. Users are required to remove the 
software from their computer if they cease paying the license fee.
 ? l icense with Maintenance offer “maintenance” or “software assurance” along with 
the original license fee.
1.5 Cyber law
Cyber law is a new branch of law and is growing very fast. It establishes norms of accepted 
human behaviour in cyberspace. There are three basic building blocks of cyber law.
 ? Netizens who are the inhabitants of the internet and 
use it as an extension of their physical world
 ? Cyberspace which is a ‘man made machine world’ 
reshaping itself periodically. 
 ? Technology
Cyber law includes all the cases, written rules and government laws that affect persons 
and institutions who 
 ? control the entry to cyberspace, 
 ? provide access to cyberspace, 
 ? create the hardware and software which unable people to
  ? access cyberspace or 
  ? Use devices to go ‘online’ and enter cyberspace.
Laws governing ecommerce, online contracts, copyright, trademark, business software 
patenting, eTaxation, eGovernance and cyber crimes all fall within the meaning and scope 
of cyber law.
1.6 Cookies 
Cookies allow a visited website to store its own information about a user on the user’s 
computer. 
Page 5


109
Network Security
Chapter 6
Network Security
Learning Objectives 
By the end of this chapter, learner will be able to:
•	 Name	 the	 diff er en t	 kinds	 of	 softw ar e	 licensing	 a v ailable
•	 Diff er en tia t e	 be tw een	 fr ee w ar e	 and	 open	 sour ce	 softw ar e
•	 St a t e	 ho w	 the	 use	 of	 shar e w ar e	 softw ar e	 is	 diff er en t	 fr om	 tha t	 of	 fr ee w ar e	 softw ar e
•	 Diff er en tia t e	 be tw een	 c op yrigh t	 and	 licensing
•	 De fine	 cyber e thics,	 cyber sa f e ty	 and	 cyber security
•	 St a t e	 the	 purpose	 of	 c ookies
•	 T abula t e	 the	 diff er en t	 phases	 of	 cyber	 e thics	 e v olution
•	 Lis t	 pr ec autions	 tha t	 c an	 be	 t ak en	 t o	 ensur e	 cyber	 sa f e ty
•	 Iden tif y	 the	 diff er en t	 kinds	 of	 thr ea ts	 t o	 cyber	 security
•	 St a t e	 e thic al	 beha viour	 t o	 be	 f ollo w ed	 as	 a	 cyber	 citiz en
•	 Iden tif y	 the	 diff er en t	 c a t eg ories	 of	 cyber	 crime
IntroduCtIon
The world created by technology is one of machines - computers, computer systems and 
computer networks. Add to that the human component and one has a world of diverse 
cultures and social practices that is often referred to as cyberspace. 
Cyberspace is a man made world that is constantly evolving. It differs from the static 
physical world as it has no boundaries, no geographical mass, and of course, no gravity. It is 
limitless, constantly changing its shape, attributes and characteristics. It exists in a form of 
bits and bytes; it is an information driven world. Government(s), hardware manufacturers 
and software application providers act as gatekeepers of cyberspace. 
This medium, which is dynamic, infinite and intangible has to be regulated to prevent 
it from exploding. Regulating cyberspace means regulating both man and the machine. 
There is ethics, safety and security involved. 
Ethics represents personal choice. It’s the set of acceptable behaviours in a given culture. 
It’s not just a list of rules but the code of conduct by which a society chooses to live. Safety 
refers to safe practices and security is the additional tasks carried out to ensure safety. 
110
Information and Computer Technology
The first is a moral choice, the second a behavioural code and the third involves active 
participation.
in cyberspace we have 
 ? Cyberethics exploring appropriate and ethical behaviours related to online 
environments and digital media. It includes plagiarism, bullying, and hacking to 
name a few.
 ? Cybersafety defining how one operates on-line. It includes rules guiding how to keep 
personal information safe and limited
 ? Cybersecurity involving tasks undertaken on the computer to keep it secure from 
people who wish to harm it or use data stored on it unlawfully. This includes installing 
virus software and firewalls.
Before we study these in greater detail there are certain fundamental terminology and 
concepts that must be understood.
1. BaSIC terMInoloGy 
1.1 Copyright and license
Copyright is about protecting original expression. Copyright 
arises as soon as a ‘work’ is created. A software copyright 
protects all source code, written text materials, graphic 
images/ designs, drawings, any linked sound, video files 
or films.
A copyright owner has five exclusive rights: 
 ? Fix or store the information in a tangible form.
 ? Reproduce the copyrighted material. 
 ? Sell, rent, lease, or otherwise distribute copies of the copyright work to the public.
 ? Publicly perform and display the copyrighted material.
 ? Prepare derivative works based on the copyrighted material.
l icense is the permission granted by the holder of a copyright to another to use an 
original work. It states under what circumstances and to what extent the original work 
can be used, changed or distributed. It may include a period of time, a geographical area, 
renewal provisions, and other limitations. It does not pass on the copyright. 
111
Network Security
1.2 Software licensing
A software license is a legal agreement about an 
application. It is between the software producer and 
the end-user and is an important part of the legally 
binding contract between them (or rights owner) 
and the end-user. This is to ensure recognition of the 
rights of the owner on his creation. It specifies how 
the application may be used and defines the rights of 
both the producer and the user. 
1.3 open Source, freeware and Shareware 
o pen-source software (OSS) is computer software with its source code made available. It is 
very often developed in a public, collaborative manner. A license for open sources software 
allows the end user to study, change and distribute the software for any purpose. 
Some copyrighted software is made available for use, free of charge for an unlimited time. 
These are called freeware. The copyright still remains with the producer / owner for any 
future development. 
s hareware are copyrighted software that can be shared for a limited on a trial basis with 
the understanding that if the user decides to use it, he will pay for it. 
1.4 t ypes of software licenses
 ? Proprietary license where the copyright stays with the producer and the user is 
granted the right to use the software
 ? gnu g eneral Public l icenses, which are agreements under which “open source” 
software is usually licensed. It allows end users to change the source code, but the 
changed code too, must also be made available under a GNU GPL license.
 ? e nd u ser l icense a greement (EULA) indicates the terms under which the end-
user may use the software.
 ? Workstation licenses are licenses that permit the installation of an application on 
a single computer. Before installing it on a different machine the software must be 
removed from the first machine
 ? Concurrent use licenses permit the installation of the software onto multiple 
machines as long as the number of computers using the software at the same time 
does not exceed the number of licenses purchased.
112
Information and Computer Technology
 ? site licenses permit the use of software on any computer at a specified site. Unlimited 
site licenses allow the installation of the software on any number of computers as 
long as those computers are located at the specified site.
 ? Perpetual licenses come without an expiry date and allow the software to be used 
indefinitely
 ? n on-perpetual licenses “lease” the software for use for a specified period of time, 
usually annually or sometimes bi-annually. Users are required to remove the 
software from their computer if they cease paying the license fee.
 ? l icense with Maintenance offer “maintenance” or “software assurance” along with 
the original license fee.
1.5 Cyber law
Cyber law is a new branch of law and is growing very fast. It establishes norms of accepted 
human behaviour in cyberspace. There are three basic building blocks of cyber law.
 ? Netizens who are the inhabitants of the internet and 
use it as an extension of their physical world
 ? Cyberspace which is a ‘man made machine world’ 
reshaping itself periodically. 
 ? Technology
Cyber law includes all the cases, written rules and government laws that affect persons 
and institutions who 
 ? control the entry to cyberspace, 
 ? provide access to cyberspace, 
 ? create the hardware and software which unable people to
  ? access cyberspace or 
  ? Use devices to go ‘online’ and enter cyberspace.
Laws governing ecommerce, online contracts, copyright, trademark, business software 
patenting, eTaxation, eGovernance and cyber crimes all fall within the meaning and scope 
of cyber law.
1.6 Cookies 
Cookies allow a visited website to store its own information about a user on the user’s 
computer. 
113
Network Security
When a user uses a computer to visit a website, the website stores some basic information 
about the visit on the hard disk of the computer. It records the user’s preferences while 
using the site. This stored information is called a ‘cookie’ .
1.7 Hackers and Crackers
Hackers are people with computer programming skills who use their knowledge to gain 
unauthorized access to data in a system or computer. 
Crackers modify or disable features of a software 
application. They usually mean to harm the software, 
the hardware using this software or the end user of the 
software. 
Both hackers and crackers can also work on the ethical side when they use their skills to 
prevent cyber crime and help the law keepers.
1.8 firewall 
A firewall is a program or hardware device that 
filters the information coming through an internet 
connection to a network or computer system. If 
incoming information does not pass the rules 
stored in the firewall, it is not allowed through.
1.9 Cyber ethics
The explosion of social networking and the common practice of sharing and posting of 
information online have changed the way people communicate. Users must understand 
their responsibilities for conducting themselves online. An important component of that 
is Cyber Ethics. Cyber Ethics refers to the code of responsible behaviour on the Internet. 
Basic Cyber ethics must be followed to be good cyber citizens. 
Cyberethics began in some form in the 1940s. It examines the impact of not only the 
internet or computing machines but also private computer networks and interconnected 
communication technologies.