What Is A Domain Name?

A domain name is a human-readable string that points to a numeric IP address: the actual location of a website or server on the internet. Nobody wants to remember a string of numbers to visit a website, so domain names exist to translate those addresses into something people can read, say out loud, and remember.

Before search engines were any good, people found websites by guessing, typing in whatever.com just to see what came up. Search engines changed that, and now AI is changing it again, with people asking an AI assistant to find or describe a website instead of typing a URL or running a search themselves. The way people find a website keeps changing, but the website still needs an address to be found at. That's what a domain name is.

Who's Allowed to Invent an Extension?

Nobody can just decide to launch a new extension. ICANN, the Internet Corporation for Assigned Names and Numbers, is the global body that decides which top-level domain extensions are allowed to exist at all. Every extension in use today, from .com to .au to .pizza, exists because ICANN approved it.

From a Handful to Hundreds

In the 1980s there were only a handful of extensions: .com, .edu, .gov, .mil and .org, with .net added soon after. ICANN approved a major expansion of the system in 2008 and opened applications for new extensions in 2012. Since then, the number of generic extensions has grown past 1,200, covering everything from industries to hobbies to made-up brand words.

On top of that, almost every country has its own country-code extension, like .au, .uk or .fi, each run under its own local rules by its own national registry. In Australia, that's auDA, the body that administers the .au domain space and accredits the registrars allowed to sell it.

Every one of these extensions is run as a business in its own right. A registry operates the infrastructure behind an extension and charges a wholesale fee for every domain registered under it. Verisign operates .com and .net, Public Interest Registry operates .org, auDA operates .au: different businesses, different extensions, the same underlying model.

More Than Just a Website

A domain name's best-known job is pointing a web browser to a website, but that's not all it does. The same domain can be configured to answer other kinds of requests too, like FTP for file transfer, not just a browser asking for a webpage.

A domain is also what turns a name into an email address. gmail.com is owned by Google, which is exactly why Google can hand out free addresses on it, like user.surname@gmail.com. A domain you own works the same way: whatever@yourdomain.com.au is configured through that same domain.

Picking the Right Extension

.com has been around the longest and has the greatest uptake of any extension, which is exactly why the best .com names are so scarce and expensive. It isn't the only sensible option though:

There are also newer extensions that let a domain span across the dot itself, instead of sitting in front of it. A running events directory could register running.events, reading as one phrase rather than a domain plus a category. These are all part of what the industry calls the new gTLDs: generally far cheaper than .com, and often available for instant registration if the exact word you want is free.

Why .com Still Wins

None of that changes the fact that .com is still the most desired extension, and usually the smartest one to own if the exact name is available. A new gTLD can still leave people confused about what to type, especially anyone unfamiliar with it.

It comes down to memorability. .com is the assumed extension, the one people type without even thinking about it when they can't recall anything else about an address. That means a .com domain only really asks someone to remember one thing: the SLD, the actual name in front of the dot. Any other extension asks for two things to be remembered, the name and which less obvious extension it happens to sit on, and that second detail is exactly the kind of thing people forget, or guess wrong.

That's why it's often smarter to make a domain longer with a compound word on .com than to chase an alternative. A plumbing business called Atlas is better off on AtlasPlumbingCo.com than fighting for atlas.com, which is both extremely expensive and realistically never becoming available. It's also better off there than on AtlasPlumbing.co, since people will keep typing, and emailing, AtlasPlumbing.com by habit, sending traffic and messages to a domain the business doesn't even own.

A domain name is just an address with a brand attached, and like any address, the extension is part of what people remember it by.