Some important Concept
1G Mobile Systems: The 1G Mobile System was introduced in late 1970s and early 1980s.The 1G mobile
system was based on the analog cellular technology. They only had voice facility available.
2G Mobile Systems: They used digital signals for transmissions of voice. 2G enabled the mobile systems to
provide paging, SMS, voicemail and fax services.
3G Mobile Systems: The 3G technology adds multimedia facilities to 2G phones by allowing video, audio,
and graphics applications.
4G Mobile Systems: 4G will provide better-than-TV quality images and video-links.
Virus: Virus is a malicious program that attaches itself to the host program. It is designed to infect the host
program and gain control over the system without the owner’s knowledge.
Worm: Worm is also a malicious program like a virus. But unlike viruses, it does not need to attach itself to
a host program. A worm works by itself as an independent object.
Trojan horse: A Trojan horse is a program that contains hidden malicious functions. Trojan Horses trick
users into installing them by appearing to be legitimate programs.
Spam: The term spam means endless repetition of worthless text. In other words, unwanted messages or
mails are known as Spam.
Cookies: This small text file is a cookie. Generally a cookie contains the name of the website that it has come
from and a unique ID tag.
Firewall: A firewall is hardware or software based network security system. It prevents unauthorized
access (hackers, viruses, worms etc.) to or from a network.
Cyber Crime: Cybercrime is defined as a crime in which a computer and internet is used in an illegitimate
way to harm the user.
Cyber Law: Cyber law is an attempt to integrate the challenges presented by human activity on the internet
with legal system of laws applicable to the physical world.
Intellectual property rights are the rights given to an individual over the invention of their own. They
usually give the creator an exclusive right over the use of his/her creation for a certain period of time
Intellectual property rights (IPR) Issues: Intellectual property rights are the rights given to an individual
over the invention of their own. They usually give the creator an exclusive right over the use of his/her
creation for a certain period of time. There are only three ways to protect intellectual property.
Hacking: The term was used for people who engaged themselves in harmless technical experiments and
fun learning activities.
Cracking: Cracking can be defined as a method by which a person who gains unauthorized access to a
computer with the intention of causing damage.
HyperText Transfer Protocol (HTTP): HTTP is the protocol that is used for transferring hypertext (i.e. text,
graphic, image, sound, video etc.) between two computers and is particularly used on the World Wide
Web. It is a TCP/IP based communication protocol and provides a standard for Web browsers and servers
WWW (World Wide Web): WWW can be defined as a hypertext information retrieval system on the
Internet. Tim Berners -Lee is the inventor of WWW. WWW is the universe of the information available on
Web page: Web page is an electronic document designed using HTML. It displays information in textual
or graphical form. It may also contain downloadable data files, audio files or video files.
A web page can be classified into two types:
Static web page
Dynamic web page
Website: Related webpages from a single wen domain is termed as a website. A website has multiple
webpages providing information about a particular entity.
Web browser: Web browser is software program to navigate the web pages on the internet. A bowser
interprets the coding language of the web page and displays it in graphic form.
URL (Uniform resource locator): Web address of the web page written on the address bar of the browser is
known as the uniform resource locator (URL).
Web hosting: Web hosting is the process of uploading/saving the web content on a web server to make it
available on WWW.
Web 2.0: Web 2.0 refers to new generation of dynamic and interactive websites. Web 2.0 websites uses a