The Domain Name Server or DNS is a system that stores information about hostnames and domain names in a kind of distributed database on networks, such as the Internet. Most importantly, it provides a physical location (IP address) for each hostname, and lists the mail exchange servers accepting e-mail for each domain.
The DNS provides a vital service on the Internet as it allows the transmission of technical information in a user-friendly way. While computers and network hardware work with IP addresses to perform tasks such as addressing and routing, humans generally find it easier to work with hostnames and domain names in URLs and e-mail addresses. The DNS therefore mediates between the needs and preferences of humans and of software.
Domain Name System are the Internet's equivalent to a phone book. A Domain Name System Server maintains a directory of domain names and matching IP addresses. The information from all the name servers across the Internet is then gathered in the Central Registry. Host companies check in with the Central Registry on a regular schedule to get updated name server information, which makes it possible for people across the Internet to access your web site. When your domain is set up, information about your domain name is added to our name servers. That information is then sent from us to the Central Registry to be used by the other name servers on the Internet.
It usually takes about 48 hours before name servers on other networks will be able to access the information after the Central Registry gets it. This 48-hour period is referred to as propagation.