People use the two words as if they mean the same thing, but they don't. The internet is the roads — a vast mesh of cables, fibres and radio links joining millions of computers into one worldwide network. The web is just one of the things that travels on those roads — the pages you open in a browser. Email travels on the same roads. So do video calls, games and the messages on your phone. The web is one passenger; the internet is the whole road system.
The internet came first, by twenty years. The web — pages you click between, with links — was invented in 1989 by a British scientist, Tim Berners-Lee, working at a physics lab in Switzerland. He built it on top of the internet that already existed. So when you "go online", you are using the internet; when you open a page in a browser, you are using the web that rides on it.
The internet is the network of connected computers — the roads. The web is the collection of pages you read on a browser — one kind of traffic on those roads. Every website needs the internet; not everything on the internet is a website.
The very first web page is still online today, at its original address. Tim Berners-Lee wrote it in 1991 to explain what the web was — a page describing the thing you were reading it on. It had no pictures, just plain text and a handful of links, and it quietly started everything you do online now.
Before we look at the parts, watch the whole thing once. Listen for one idea you've just met — that the internet is a network of networks, roads joining computers — and one you're about to meet: that your message travels as small pieces, not in one lump.
Here is the surprising part. When you send a photo to a friend, the photo does not travel across the world as one object. The computer chops it into hundreds of tiny pieces called packets. Each packet carries a small slice of the photo, the address it is going to, the address it came from, and a number saying which slice it is — slice 1 of 200, slice 2 of 200, and so on.
Each packet then sets off on its own. They don't even have to take the same route — one packet might cross the Atlantic one way, the next packet another, depending on which cables are busy. They can arrive out of order. None of that matters, because each packet is numbered: the computer at the far end simply waits for them all, sorts them back into order, and rebuilds the photo. This whole method is called packet-switching, and it is the clever idea the entire internet rests on.
Small parcels share the roads fairly. If one huge file hogged a cable, everyone else would wait. With packets, lots of people's data can be interleaved on the same wire — and if one packet gets lost, only that little piece has to be sent again, not the whole file.
Packet-switching was invented partly so a network could survive damage. If one route is cut, the packets simply flow around the gap by another path — like water finding a way downhill. There is no single wire the whole internet depends on; that was the design idea from the very start.
For a packet to find its way, every computer on the internet needs a unique address — the way every house needs a postcode. That address is called an IP address, and it is just a number, usually written as four numbers with dots between them, like 142.250.72.78. Every packet carries the IP address it is going to, and the routers along the way read that address and pass the packet onwards, hop by hop, until it arrives.
But nobody wants to remember 142.250.72.78 to visit a website. We remember names — like bbc.co.uk. So the internet keeps a giant phonebook that turns names into numbers. It is called the DNS — the Domain Name System. When you type a name, your computer first asks the DNS, "what's the number for this name?" The DNS answers with the IP address, and only then can your packets set off.
The old style of IP address (four numbers, 0–255 each) gives about 4.3 billion different addresses — and the world ran out of them, because there are more connected devices than that. A newer system called IPv6 has so many addresses that you could give one to every grain of sand on Earth and barely make a dent.
When you open a page, two computers are talking. Yours is the client — the one doing the asking. The computer that stores the website and sends it back is the server — the one doing the answering. The client makes a request ("please send me this page"); the server gives a response ("here it is"). That back-and-forth is the shape of almost everything online.
The language they speak is called HTTP — the HyperText Transfer Protocol. A protocol is just an agreed set of rules for a conversation, so that any client and any server in the world can understand each other. When you see https:// at the start of a web address, the s means secure — the conversation is scrambled so nobody in between can read it. That padlock in the address bar is HTTP, locked.
A protocol is an agreed set of rules for how two computers talk, so any pair can understand each other anywhere in the world. HTTP is the protocol for web pages; there are others for email, for video, for files. Agreeing the rules in advance is what lets the whole internet work together.
A single big server doesn't really sit in one room somewhere. Popular websites are stored on thousands of servers in buildings called data centres spread across the world — so the copy that answers you is usually one of the closest, to keep the page quick. Some data centres are the size of several football pitches.
Now put it together. Here is the entire journey, from the moment you type a name to the moment the page appears — and it all happens in well under a second.
Tap each card — the job each part does on the journey:
This short film follows packets across the network — the very idea you've just met. Watch for two things: how the message is broken into pieces, and how those pieces find their own separate routes to the same place.
Press Next step to walk a single packet through the whole journey — from your computer, through the DNS lookup, across the routers to the server, and back again with the page.
In real life all of this happens in a fraction of a second — and a real page is hundreds of packets, not one. Stepping through one packet shows the shape of the journey they all take.
Because the internet joins everyone to everyone, the same roads that carry a kind message can carry an unkind one, and the same server that holds a real page can be faked. A few calm habits keep you safe: look for the https padlock before you type anything private; be slow to trust a link or a message that arrives out of the blue; and never give a password to a page you reached by clicking rather than typing the address yourself. None of this should make the internet feel frightening — it is, mostly, a kind and useful place. It just rewards a little care.
Staying safe online deserves more than a paragraph — there is a full lesson on it. When you've finished here, have a look at Staying safe online for the proper version: spotting fakes, strong passwords, and what to do if something feels wrong.
The padlock and the s in https don't just lock the conversation — they also prove the server really is who it claims to be, using a kind of digital ID card called a certificate. A browser quietly checks that ID every single time, before the page even loads.
Fresh one. What is the name of the internet's "phonebook" — the system that turns a name like bbc.co.uk into an IP address number? (Three letters.)
Imagine telling a younger cousin who has never thought about it. Start from typing the name and follow it all the way to the page appearing. Four or five sentences is plenty. Try to use, in your own way, the words DNS, IP address, packets and server — and keep the steps in order.
strong You held the order all the way down — name, then the DNS lookup, then packets to the server, then the page coming back. That order is the whole point of the lesson, and you kept hold of it. Naming the DNS as the "phonebook" in your own words shows you've understood what it's for, not just what it's called.
try this One sentence carries two steps at once — the DNS lookup and the packets setting off — which makes it move a little fast. Give the packets their own sentence: split into numbered parcels, each finding its own way. Slower there reads clearer.
to add You could close with the line that makes it land: all of this happens in less than a blink, hundreds of times, every time a page fills in. That last sentence turns a list of steps into a real sense of the scale.
Sit down with Dad for any of these. They show where the internet came from and the people who built it. Heavier titles flagged for a chat first.
Three short films to watch alongside today's lesson — each shows you something the words and pictures can't.
You learned that the internet is the roads and the web is just one kind of traffic on them. You saw how a file is cut into numbered packets that each find their own way; how every machine has an IP address and the DNS turns names into those numbers; and how a client asks a server, in the language called HTTP. Next time a page fills in, you'll know the journey behind it. Florence, this is computing.
Most of the internet between continents doesn't travel by satellite at all — it runs through cables on the seabed, some thinner than a garden hose, laid across the ocean floor. There are hundreds of them, carrying nearly all the world's data between continents. A ship's anchor in the wrong place can slow a whole country's internet.