In order for the internet to work, domain names are essential. Your website cannot be easily found without a domain name. The domain name system (DNS) is used for converting human friendly names to IP addresses. A hostname or fully qualified domain name (FQDN), identifies a specific device within the DNS namespace, for example www.example.com identifies the device 'www' within the example.com domain.
The process of claiming a domain name within the public DNS infrastructure is called domain name registration. It's a very simple procedure, costing very little these days. If you want to run a website a domain name is an essential prerequisite. There are many levels to the domain name system. A top level domain creates the basis of all internet registered domains. Top-level domains include:
+ many more.
Top level domains can have many secondary level domains, for instance domain1.com, where domain1 is this second level domain.
Nowadays there are numerous domain name extensions available for use. During the early days of the internet, there were just a few like .com, .net, .org, etc. Now many more extensions have become available, for example .me, .tv, etc., due to the huge increase in web sites being built.
There is a specific naming convention used for all domain names without exception. A domain name has the following restrictions:
- Must use ASCII letters (A-Z and 0 to 9)
- Maximum 255 characters in total.
- Can include hyphens (-)
A domain tree is created by separating each level of the domain with a period (.) character.
Most domain names can be registered on a yearly cycle, but it is recommended that you register your domains for as many years as you can manage upfront. However, some domain extensions do not allow you to register on a yearly basis and demand that you pay for a minimum of two years registration in advance. One example of a domain extension that does apply this restriction is the .co.uk domain.
Computing devices use IP addresses, such a 192.168.0.1 to exchange data with one another, however, remembering these addresses is difficult for humans, so the Domain Naming System (DNS) converts human friendly names to IP addresses. There is another service for changing IP addresses to domain names, called reverse DNS (rDNS). The system is employed to match up IP addresses to domain names, i.e. the contrary of DNS.