WHAT IS A NETWORK?National 4/5 Computing Science

LESSON AIMS By the end of this lesson you will be able to:

Describe what a network isDescribe what a stand alone machine is

Explain what a LAN and WAN is

Describe the difference between the internet and the World Wide Web

What is a network?

BACK IN THE DAY…

When I went to school the computer’s were not connected. We had to use the same computer every time

ANY ISSUES WITH STAND ALONE MACHINES?

What if ‘your’ computer fails

Someone else is using your machine?

You have 130 computers and need to install some software.

NETWORKS

A network is a series of computers that are connected so that they can send and receive data.

The first information was sent between computers in 1969 between the University of California and Stanford University

TYPES OF NETWORKS

Local Area Network (LAN) This is a network that connects computers in a

small area/single building Can be wired or wireless

Wide Area Network (WAN) This is a network that connects computers over

large distances such as in different towns and countries. The internet is an example of a WAN.

Are usually connected by telecoms links(phone wires/fibre optics) or satellites.

SAMPLE LAN

SAMPLE WAN

ADVANTAGES OF NETWORKS

They can be expensive to create so why bother with them?

Why does the school have a LAN?1. Networks make it easier to share data2. Networks allow expensive peripherals such as

printers and scanners to be shared3. Can allow communication via email

QUESTION

How many of you have the internet at home?

None of you have!

You have access to the world wide web! More on this later…