- Define and explain What Is a Network? in your own words
- Use key terms such as network accurately
- Apply what you have learned to new examples and questions
- Avoid the common mistakes learners make with this topic
Every message, video call and game update you send travels across networks of computers — sometimes around the entire planet in a fraction of a second. Networks are the invisible roads of the digital world. This chapter follows your data on its journey and shows how it stays safe along the way.
This lesson focuses on What Is a Network?: explore LANs, WANs and the hardware that connects devices.
Explore LANs, WANs and the hardware that connects devices.
Key ideas
The internet is a network of networks
Your home network connects to your internet provider's network, which connects to other providers' networks across undersea cables and satellites. No single company owns the internet — it is millions of networks agreeing to exchange packets with each other.
Protocols keep everyone compatible
Devices from thousands of manufacturers can communicate because they all follow the same protocols, such as TCP/IP. A protocol defines exactly how packets are addressed, sent and acknowledged — without these shared rules, the internet would be a tower of Babel.
Key term — network: Two or more devices connected so they can share data and resources, from a home Wi-Fi to the entire internet.
What is the difference between a LAN and a WAN?
A LAN connects devices in a small area like a home or school; a WAN spans large distances — the internet is the biggest WAN of all.
Answer: A LAN connects devices in a small area like a home or school; a WAN spans large distances — the internet is the biggest WAN of all.
- Thinking the internet and the World Wide Web are the same thing Correction: the internet is the network of connected devices; the Web is just one service — pages and links — that runs on top of it, like email and streaming do.
- Assuming packets arrive in order Correction: packets take different routes and arrive jumbled — numbering lets the receiver sort them out.
Practice
Wi-Fi is just the wireless link between your device and the router; the internet is the global network beyond the router that your data travels across.
True — addresses must be unique so packets reach the right device, just as post needs a unique address per house.
It scrambles the data so anyone intercepting the packets sees only meaningless noise without the key to unscramble it.
Only the missing packets need re-sending instead of the whole video, and packets can travel different routes to avoid congestion.
Quick check
Which of these best defines "network"?
What must every packet carry so routers can deliver it — and what everyday item does this resemble?
- What Is a Network?: explore LANs, WANs and the hardware that connects devices.
- The internet is a network of networks: Your home network connects to your internet provider's network, which connects to other providers' networks across undersea cables and satellites.
- IP address: A unique numerical label for a device on a network, so packets know where to go — like a postal address.
- Watch out for: thinking the internet and the World Wide Web are the same thing