DNS: The Domain Name System
The Internet Protocol address is a 32- bit integer. If somebody wants to send a message it is necessary to include the destination address, but people prefer to assign machines pronounceable, easily remembered names (host names). For this reason the Domain Name System is used. These logical names also allow independence from knowing the physical location of a host. A host may be moved to a different network, while the users continue to use the same logical name.

Internet Protocol Addressing

Each machine connected to an IP network (such as the Internet) is addressed using a unique 32 bit number, the IP address

Domain Name Server - dns Setup and Configuration

Now a days when there are thousands of computers in a network it is not possible to remember the ip address of each system. Domain name system provides a convenient way of finding computer systems in network based on its name and ip address. Domain name services resolves names to the ip addresses of clients and vice versa. Domain name system is a hierarchical system where we have a top level domain serving sub domain and clients with names & ip address.