What is a Domain Name? Before we can go into what a domain name is I'm going to tell you why we need them as the answers compliment each other. The Internet is just a really big collection of connected computers (a network). For the purpose of explaining domain names you can think of the Internet a bit like the phone system and just like the phone system every computer on the Internet has it's own phone number except an Internet phone number is called an IP addresses. This address is made up of up to 12 digits in the form 123.123.123.123, computers use these IP addresses to send information to each other over the Internet.
When the Internet was first created it quickly became clear that these IP addresses were not easy to remember and another method was need to make these addresses more human friendly. The solution to this was the Domain Name System (DNS). Basically the DNS is a really really big phone book for computers. When you type a web site address into your web browser it checks the DNS for that website name and finds the IP address. Once it has the IP address it can then send a message to that computer and ask it for the web page you wanted.
Ok so you know a domain name is part of a web site address but which part? Lets look at a website address so we can identify and discuss what bit of it is a domain name.
<a href="http://www.itxcel.com/index.html" target="_new">http://www.itxcel.com/index.html</a>
The above address is the home page of the itXcel web site. It can be split into 3 main parts. The first part is http:// this just tells your web browser what kind of information it is going to get and how to get it. The last part is /index.html this is name of the files on the remote computer that you want your browser to get. The bit in the middle <a href="http://www.itxcel.com" target="_new">www.itxcel.com</a> is a domain name. This is the name that your computer sends to the DNS to get back the IP address.
So you know what a domain name is and that there is a phone book called the DNS to change your easy to remember domain name into an IP address that you computer can understand. The Internet phone book (DNS) is special in that everyone on the Internet needs to be able to use it. This makes the DNS very very big (100+ million addresses big). Due to the size of this phone book it needed to have a carefully organised and managed structure.
Domain names themselves are split into different levels like a hierarchy. The DNS system uses this hierarchy to search the DNS for the IP address of the domain name it is trying to find. The last bit of a domain, in the previous example the com part is called the top level domain. There are a large selection of top level domains like com, net, org and info. There are also very similar endings called country level domains like uk and de. Each of the top level and country level domains are managed by a different organization, sometimes these are companies or non profit organizations and sometimes governments. In the domain business these organisations are referred to as the registries. Each registry looks after it's own part of the domain name system.
If you decide you want to use a domain name in the top level domain com, like mycompany.com you would have to have this name assigned by the registry that manages that top level domain (for .com a US company called VeriSign). The process of being assigned a domain name is called domain registration.
Domain registration is more like a lease than a purchase. You are renting the second level domain (the mycompany bit) from Verisign for a specific amount of time normally between 1 and 10 years at a time. Most of the organizations that allow you to register a second level domain charge a fee for each year that you register the domain for. With almost all domain names you are also given the option to renew your registration (lease) when it is close to running out (expiring).
Once you have registered a second level domain you are free to create as many third level domains (sometimes called sub domains) as you like. In our previous example the www is a sub domain of itxcel.com.
Most of the registries that manage these top level domain names do not allow individuals or businesses to register domains directly with them. To register a domain you need to use a company like itXcel. We act as a registrar and send all the required information and the registration fee to the registry. Registrars are useful as they hide the differences that exist in each of the registries from the customer and provide a simple step by step process for registering a domain. A registrar also allows you to manage and track all your domains from one place rather than having to deal with a different company for each top level domain.
OK so I know what a domain name is, Why do need one? Can you image what a nightmare it would be if you had an email address like myname@123.246.128.255 or a web site address http://123.246.128.255/? These addresses are possible but not very easy to remember. Now if you register a domain name you could create an email address like myname@mycompany.com and a web site address like mycompany.com. These are much easier to remember and look 100 times more professional.
One of the important points about registering a domain is that once done you have an exclusive right to use that domain for as long as you keep the domain registered in your name. If you do not renew a domain at the end of it's registration period it will again become available for registration by someone else. For this reason even if you don't want or need a web site at the moment, it's still a good idea to register a domain as soon as possible. Just imagine if your competition registered the domain name of your company or product. Although there is a process in place to retrieve these domain it can be long and complicated. It is definitely simpler to spend a little money up front to secure your chosen domain names.
About The Author
Ewan Bain is the general manager at itXcel Internet Limited - Based in the UK itXcel provide Internet services, including domain name registration and web site hosting to small to medium sized businesses and home users.
To find out what domains are available and to quickly and cheaply register them visit <a target="_new" href="http://www.itxcel.com">http://www.itxcel.com</a> now and enter your desired name in the domain search box.
For further information please visit our website.
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