This document contains a worksheet on computer networks and internet applications for 8th standard students. It includes questions about computer network topologies like star, bus, ring and tree. It also discusses the differences between local area networks and wide area networks. There are questions on internet concepts such as search engines, e-commerce, types of software. Applications like email, chatting, video conferencing and security threats like viruses are explained.

1. JNYAN VIKAS SCHOOL
Computers- Worksheet 1
2014-2015
Lesson: Computer Networks
Name: Std: VIII
Roll No: Date:
Q1. Fill in the Blanks:
1. A network that covers two or more Local Area Networks are called Metropolitan area network
2. NIC is an acronym for Network Interface Card.
3. Individual machines in a network are called Node
4. A PC which is not connected to any other computer is called Stand-alone machine
Q2. Answer the following.
1. Define Computer networks
A computer network is defined as multiple computers connected together for purpose of communicating
With each other and sharing of data and resources.
2. Define Topology
Topology refers to the arrangement of computers in a network. Based on topologies, networks can be
classified as Star, Bus , Ring, Mesh , Tree.
3. Describe the Star Topology
In Star Networks, all computers are connected by cables to a central device called the Server. The server
controls all the functions of the network. Any information which has to be transferred from one computer
to the other on the network has to go through the server.
This topology is easy to install, but if the server fails the network is disabled.
4. Draw a labeled diagram representing the Ring, Bus and Tree and Mesh topology
5. The two main strategies for connecting computers are:
 Client/Server
 Peer-to-Peer
Briefly describe each strategy with diagrams.

2. Client/Server Network Peer-to-Peer Network
In this type, there is a centralized
powerful computer called the server
which does all the processing.
All the nodes in the network known as
clients are connected to the server.
The server controls the network
These networks are expensive to setup.
In this type there is no server machine.
There is a direct connection between the nodes.
This architecture is better for smaller networks.
It is easier to setup and maintain.
6. What is the difference between LAN and WAN. Give examples of each.
LAN WAN
Local Area Network Wide Area Network
It covers a small geographic area like a
home, office or building
Covers a broader geographic area across
countries or even continents
Eg. School, Office networks Networks of Banks with e-banking, networked
offices of multinational companies and the
Internet
7. Write a short note on the Advantages of Networking.
Children are expected to elaborate on the following advantages
1. Communication
2. Sharing of Hardware and Resources
3. Data Sharing
4. Sharing Softwares.

3. JNYAN VIKAS SCHOOL
Computers- Worksheet 2
2014-2015
Lesson: Internet Applications
Name: Std: VIII
Roll No: Date:
Q1. Fill in the Blanks
1. Write the full forms of
a. URL Uniform Resource Locator
b. RSS Really Simple Syndication.
2. Examples of Search Engine are Google.com, Altavisa.com, Yahoo.com, Khoj.com
3. Buying and selling of Goods and services on the internet is referred to as E-Commerce
4. The Internet Watch Foundation (IWF) was established to focus on removal of illegal material from the
internet.
Q2. Match the following
1. Freeware a. A software which can be
downloaded for free but after
sometime you will have to pay
to use the software
2. Shareware b. A software that can be
downloaded for free and used by
anybody
3. Trialware c. A new software that needs to be
tested.
4. Open source software d. Software in which the source
code is available for public to
use and modify.
5. Betaware e. A software which can be
downloaded for trial purpose.
b
a
e
d
c

4. Q3. Differentiate between the following
a. Chatting and Videoconferencing
Chatting Videoconferencing
Chatting is talking real time over the internet. It
is an online text conversation which is
immediately received by the receiver.
Video conferencing is a facility provided by the
internet where a group of people all over the
globe can have an online conversation where they
can hear and see each other and at the same time
exchange text messages.
Eg of Chat programs are Gtalk, Facebook chat,
Microsoft chat.
Eg. TV news reporter reporting live from a
faraway place on a talk show where participants
are in different cities.
b. Hacker and Cracker.
Hacker Cracker
Hackers are people who use their computer skills
to enter into computer systems without
authorization.
A cracker is a malicious programmer who gains
unauthorised access to computer systems for
purpose of setaling , altering or corrupting
information.
They do not have evil intentions. They intend to cause harm
Q4. Write a short note on the following
1. Virus
A virus is a program that enters into the computer system by attaching itself to another program and then
spreads itself across the system.
A virus on entering the system disrupts its functioning. It could damage the data stores abnd even cause
The computer to malfunction.
The Internet is a major source of Virus.
2. E-mail
Full form is Electronic Mail. It is a fast , easy and inexpensive way of communicating over the internet.
Emailing allows to send text, images, video, and music files to anyone who has an internet account.
To send and receive an email you need to have an e-mail account. Nowadays most websites and search
engines offer free email services. Some popular email providing websites are yahoo.com, gmail,
rediffmail, hotmail.