What a network is
Devices talking to each other
A network is two or more devices connected so they can share information. Your phone and your home's Wi-Fi router are a network. So is every computer and printer in an office. The internet is a network of networks: millions of them, connected all over the world.
| Word | Means | Example |
|---|---|---|
| LAN (local area network) | A network in one place | Your home Wi-Fi; a café's office |
| WAN (wide area network) | Networks connected over long distances | A bank's branches; the internet |
| Client | A device that asks for something | Your laptop opening a website |
| Server | A computer that provides something | The computer that sends you that website |
| ISP (internet service provider) | The company that connects you to the internet | Your NBN provider or mobile phone company |
Packets
Data doesn't travel as one big lump. It's chopped into small packets — usually up to about 1,500 bytes each. Every packet carries the address it's going to and the address it came from, like an envelope. Packets from one video call can take different routes and are put back together at the other end. If one gets lost, it can be sent again.
Why learn networking?
- IT support: "the internet's not working" is one of the most common help-desk calls
- Developers and testers need to know about addresses, ports and HTTP every day
- Everyone can set up their home network safely and fix their own Wi-Fi problems
How this course works
You'll learn each idea, try commands on your own computer, and then practise in the network lab — a small, safe practice network that runs on your computer, which you'll set up in lesson 3. Your own network will look a bit different from the examples (every network does), but the ideas are the same.
Try it
- Count the devices on your home network: phones, laptops, TVs, game consoles, smart speakers… Most homes have more than people expect.
- Which devices in your home are clients? Are any of them servers?
Downloads
1 file to download once you enrol.