How the Internet Works
You type an address and a page appears in under a second. Here's what actually happens in between, in four short lessons and no jargon.
Every device has an address
The internet is millions of networks connected together. Every device on it has an IP address, a number like 142.250.80.46, so data knows where to go, like a postal address.
Your home router has one public address on the internet and gives each of your devices a private one inside your home.
DNS: the internet's phone book
Nobody remembers numbers like 142.250.80.46, so we use names like google.com. The Domain Name System (DNS) translates the name into the IP address, much like looking up a contact to get their number.
Your computer asks a DNS server (usually your internet provider's), which looks it up and replies. The answer is remembered for a while so the next visit is faster.
That's why flushing your DNS cache can fix a site that won't load: it throws away an outdated answer. See our no-internet guide.
Packets and routers
Data doesn't travel as one big block. It's cut into small packets, each labelled with where it's from and where it's going. Routers pass each packet along, hop by hop, towards its destination, and the packets can even take different routes.
At the other end they're put back in order. If one goes missing, it's sent again. Much of this travels through undersea cables, not satellites.
Asking for the page, securely
Your browser sends an HTTP request (“please send me this page”) to the server's IP address, and the server sends back the page's files: HTML, images, styles and scripts.
The S in HTTPS means the connection is encrypted, so people in between (like others on public Wi-Fi) can't read or change what's sent. The padlock in the address bar shows it's on.
A padlock means private, not trustworthy. Scam sites can have HTTPS too. It only proves the connection is encrypted.