Name Server

Name server
             A name server or DNS is the Internet's equivalent to a phone book. A domain name server maintains a directory of domain names and their matching IP addresses. This information allows other computers to know where to go to find your website over internet. How? The information from all the domain name servers across the Internet is gathered into a Central Registry. Computer networks across the world check in with the Central Registry on a regular basis to get updates so they will know information about your domain and where to find your domain name or your website if you have one.

For example Human-readable names like "example.com" are easy for people to remember, but they don't do machines any good. All of the machines use names called IP addresses to refer to one another. For example, the machine that humans refer to as "www.example.com" has the IP address 70.42.251.42. Every time you use a domain name, you use the Internet's domain name servers (DNS) to translate the human-readable domain name into the machine-readable IP address. During a day of browsing and e-mailing, you might access the domain name servers hundreds of times!

When you type a URL into your browser, the browser's first step is to convert the domain name and host name into an IP address so that the browser can go request a Web page from the machine at that IP address (see How Web Servers Work for details on the whole process). To do this conversion, the browser has a conversation with a name server. 

When you register for a hosting account you are given the addresses of these two name servers, after which you have to log into your domain registrar account and point the domains to the appropriate address. This allows you to attach your site to your web hosting account so that it can be put live on the internet.

It takes approximately 48 hours for your new or modified information that is entered into a domain name server to make it's way across the internet.