1. National 4/5 Computing Science
What is a Network?
National 4/5 Computing Science

2. Lesson aims By the end of this lesson you will be able to:
Describe what a network is
Describe what a stand alone machine is
Explain what a LAN and WAN is
Describe the difference between the internet and the World Wide Web

3. What is a network?

4. Back in the day…
When I went to school the computer’s were not connected.
We had to use the same computer every time

5. 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.

6. 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

7. Types of networks Local Area Network (LAN) Wide Area Network (WAN)
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.

8. Sample LAN

9. Sample WAN

10. Advantages of Networks
They can be expensive to create so why bother with them?
Why does the school have a LAN?
Networks make it easier to share data
Networks allow expensive peripherals such as printers and scanners to be shared
Can allow communication via

11. 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…