What is a domain

A domain is the unique internet address under which a website, email and other services operate. It is the first thing a visitor types and the first element of a company's identity online. As a hosting provider based in Leszno, Poland, we register domains and run hosting for them, so we cover the topic from a practitioner's angle: from the definition, through the structure of an address and the types of extensions, to how DNS works and how a domain differs from hosting — everything in one place.

What is a domain?

A domain is a unique, one-of-a-kind internet address (e.g. nodea.pl) under which a website, email and FTP server are available. There is only one domain with a given name in the entire network, so it always directs a visitor to the same specific resource. The simplest way to picture a domain is as both a company's signboard and its address on the internet at the same time.

A single domain usually runs several services at once. Under the address yourcompany.com, for instance, a visitor opens the website while staff use email in the same domain — such as office@yourcompany.com. That same address also serves an FTP server for uploading files. A domain is therefore not the website itself, but the name that routes traffic to all of those services — a human-readable label instead of the server's technical address.

What is a domain made of?

A domain consists of two parts: the main name (e.g. "nodea") and the extension (e.g. ".pl") — together they form the full address nodea.pl. The main name is usually the company name, a product or a keyword, and the extension (the ending after the dot) is .pl, .com, .eu and the like. The extension typically signals the country (.pl — Poland, .de — Germany) or the purpose of the site.

The easiest way to grasp this is to break a real address down into its parts:

• shop.nodea.pl — shop = subdomain, nodea = main name, .pl = extension,
• nodea.pl — nodea = main name, .pl = extension,
• yourcompany.com — yourcompany = main name, .com = global extension.

One more term worth separating is the subdomain — an extra address within a single domain, such as blog.nodea.pl. You create a subdomain free of charge in the control panel, without registering another domain, which is why it is used to split a site into sections: a shop, a blog or a client panel. If instead of a separate section you want one address to lead to another, you use a domain redirect.

What types of domains are there?

Domains fall into four main types: national (.pl, .de), functional (.edu.pl, .gov.pl), global (.com, .org) and regional (.waw.pl). The extension decides which group a domain belongs to, and the ending you pick signals the reach and character of the site to visitors. The list below pairs each type with examples and suggests when to choose it.

• National domains — .pl, .de, .uk. They indicate the country of operation. Choose them for a company working mainly on one national market.
• Global domains — .com, .net, .org. The .com extension marks a commercial domain with international reach — choose it when you plan to operate beyond one country or build a global brand.
• Functional domains — .edu.pl, .gov.pl, .biz, .info. They point to a purpose (education, government, business). Choose them when the type of organisation should be clear at a glance.
• Regional domains — .waw.pl, .krakow.pl. They emphasise a location. Choose them for a local business tied to a specific city.

A separate group is the newer thematic extensions — .online, .shop, .art — which describe an industry rather than a country. We register domains in most popular extensions, so the ending can be matched to the market and goal of the site, not the other way round.

How does a domain work and what does DNS do?

How does a domain work? When you type nodea.pl into a browser, DNS translates that name into the server's IP address and the site loads. DNS (the Domain Name System) is the layer that turns a human-readable name into a technical IP address — a string of digits nobody has to memorise. The whole process takes a fraction of a second and runs like this:

1. you type the domain name into a browser (e.g. nodea.pl),
2. DNS finds the server IP address assigned to that domain,
3. the server at that IP address returns the site content to the browser.

Thanks to DNS you type an easy-to-remember name instead of a string of digits — it is what links a domain to the right server. When DNS stops working, a site and email become unreachable even if the server itself runs flawlessly. We expand on the query mechanism, zone records and change propagation in a separate article on the DNS system.

How does a domain differ from hosting?

A domain is the address and hosting is the place — the domain directs a visitor to the address, while hosting stores the site files and email. These are two separate products bought separately, though they work together: the domain says where to look and hosting stores what will be shown. Under a single domain (e.g. yourcompany.com) a website and hosted email can run at the same time on the same server.

• Domain — what it is: an internet address. What it does: directs a visitor to the right server.
• Hosting — what it is: space on a server. What it does: stores the site files, database and email.

In practice you first register a domain, then buy hosting, and finally connect the two by pointing the domain settings at the hosting server. We go deeper into the topic in the article on what hosting is. You can register a domain and buy hosting with Nodea when you want your own site address and company email under one consistent name.