From a technical point of view, each computer connected to the Internet has an IP (Internet Protocol) address which identifies it. This IP address is either a string of numbers in case of an IPv4 address (for example, or a string of numbers and letters in case of an IPv6 address (for example, 2001:0db8::53). Since this series of numbers is difficult to remember, the possibility of replacing these numbers with words (the domain name) has been created. A domain name is therefore a unique name that identifies an individual, a company or an organisation on the Internet. It allows you to search for a website or send emails without having to copy a long IP address.

For example, to visit the FPS Economy website, it is easier to type "" rather than its IPv4 address The "www" indicates that the domain name is being searched for on the World Wide Web.

From a technical point of view again, the URL (uniform resource locator or web address) typed in a web browser looks like this: = Préfixe.Radical.Extenstion/Page consultée

The domain name is made of two parts:

  1. the second-level domain (SLD), sub-domain or radical;
  2. the top-level domain (TLD) or extension. Top level domain names can be subdivided into two general categories:
    • generic top-level domains (gTLDs), such as ".org" or ".net". These extensions can also be trademarks or geographical names (for example, ".vlaanderen", ".berlin", ".brussels", ".gent", etc.);
    • country code top-level domains (ccTLDs) such as ".be" or ".nl". 

Before the creation in 1998 of the Internet Corporation for Assigned Names and Numbers (ICANN)  which is the global Internet regulatory authority responsible for administering and regulating the domain name system,  there were only eight generic extensions - gTLDs - (".com", ".edu", ".gov", ".int", ".mil", ".net", ".org" and ".arpa") and ccTLDs. After the addition of several new extensions in 2000 and 2004, ICANN decided in June 2011 to open up the possibilities for extensions more widely, by launching the "New gTLD Program" (see the ICANN website on this subject). There are now hundreds of extensions corresponding to brands, cities, common names, etc. Examples include ".college", ".amsterdam", ".brussels", ".army", ".bank", ".pink", ".sncf", ".bible", etc. (for more information, see the website of the Internet Assigned Numbers Authority, the IANA). Further rounds for the attribution of new gTLD’s are likely to take place in the future. 

A domain name can also include several sub-domains. This is the case, for example, with "", where "economie" is a sub-domain of "" and ".fgov" is a sub-domain of ".be".

Finally, the prefix, or "World Wide Web", is not part of the domain name. 

Usefulness of the domain name

A domain name is the key to do everything on the Internet: setting up a website, sending and receiving emails or creating an online shop.

For a company, the domain name is essential to ensure its presence on the web:

  • the domain name allows it to increase the visibility of its website, and thus the number of visitors on this site and the number of potential commercial contacts;
  • it is used to personalise email addresses and to promote the website;
  • it represents a real asset on which the company can capitalise to create value.
Last update
30 June 2021