|  DNS (Address & MX Records)|
Domain Name System (DNS) is a distributed hierarchical system for managing computer and domain names. There is no technical requirement for implementing computer and domain names but many people on the Internet expect them and by implementing them you can increase the useablity and reduce confusion. The administrator or Internet Service Provider (ISP) of a network should configure DNS with a minimum of the server names and IP addresses. This allows users on the local area network and the Internet to find the computer by name rather than IP address.
The information from your local or ISP DNS server will be available to other DNS servers on the Internet. This system allows any computer on the Internet to lookup a host or domain name and find the corresponding address.
A DNS entry is called a record and there are many different types of DNS records. Many of these record types relate to DNS management. Only two types of records will be examined here, Address and Mail Exchanger records.
Address (A) Records
Address records are used to convert names to IP addresses. The majority of DNS records are address records.
Mail Exchanger (MX) Records
The mail exchanger record redirects email to a mail server. It can redirect mail for an individual computer or an entire domain. There must be MX records for your domain, or mail addressed to your domain will not be deliverable.