The domain name system (DNS) provides a method of representing Internet Protocol (IP) addresses as text-based names. These are used as web addresses. For example, www.microsoft.com is the representation of site 188.8.131.52. Domain names are divided into the following categories:- Top-level domain name such as .com or .co.uk (Also known as Global (or generic) top-level domain names (gLTD).) - Second-level domain name. This refers to the company name and is sometimes referred to as the 'enterprise name', e.g. novell.com. - Third-level or sub-enterprise domain name. This may be used to refer to an individual server within an organisation, such as support.novell.com.