Think of your website as a building and the domain as the address on the door. The building can be demolished and rebuilt; the address stays. That's why the address is the part worth owning.

The two things people confuse

A website needs two separate things:

• A domain name — the address, davesplowing.com. Rented yearly.
• Hosting — a computer somewhere that holds the page and answers when someone visits. Paid monthly, or bundled free.

They're sold separately, they're unrelated, and either can change without the other. Confusing them is why people think changing their website means losing their address. It doesn't. See what hosting is for the other half.

How it actually works, briefly

When someone types davesplowing.com into their phone, a directory service called DNS looks up that name and answers with a number — an IP address, roughly "the computer at this address holds this page." The phone then goes there and asks for the page.

DNS is the phone book. You never touch it directly, except once, when you point your domain at your website — usually two settings called nameservers, or a couple of records. Every builder and host has a page of instructions for this, and it's the only genuinely technical bit of owning a domain.

What a domain is made of

Take davesplowing.com:

• davesplowing is the name you choose. Letters, numbers, hyphens.
• .com is the extension, or TLD. There are hundreds: .com, .net, .org, .us, .plumbing, .services.

You can also have subdomains — www.davesplowing.com or booking.davesplowing.com — which are free parts of your own domain, not separate purchases.

What it isn't

A domain is not a website. Buying davesplowing.com doesn't put anything on it; until you connect it to hosting, it points at nothing or at a "parked" page the registrar shows.

It's also not permanent. You rent it by the year, and if you stop paying, it lapses — see what happens when a domain expires.

Do you need one?

No, not to start. A free page at someone else's address — fastpages.online/daves-plowing, or a builder's subdomain — works and costs nothing. Plenty of one-person businesses run for years that way.

Get your own domain when one of these is true:

• You're printing it on a truck, a sign or 500 cards. That's a five-year decision.
• You want email at your business name ([email protected]), which requires owning the domain.
• You want to be able to move to a different website provider without changing your address.
• You're tired of saying a slash out loud.

That last one is not a joke. It's a real cost, every single time you tell someone where to find you.

The one thing to get right

Register the domain in your own name, with your own email address, on an account only you control. Not your nephew's account because he was helping. Not the web designer's account as part of a package.

This sounds paranoid until you meet someone whose business website is held hostage by a former contractor. It happens more than you'd think, and it is entirely preventable: your name, your login, your card.

Next: how to buy one, or what it should cost.