We can define DNS Resource Records simply as DNS Server database entries. Resource Records are usually a name to IP Address (IPv4 or IPv6) mapping (or vice versa). DNS Resource Records are used to answer DNS client queries. Resource Records are added to the DNS server for the portion of the DNS namespace which the DNS Server is hosting.
There are different types of Resource Records. Most important types of Resource Records are 1) IPv4 host address (A), 2) IPv6 host address (AAAA, pronounced "quad-A") 3) CNAME (Alias), 4) Pointer (PTR), 5) Mail Exchanger (MX) 6 ) Service (SRV)
|DNS Resource Record Type
|| IPv4 Host Record, used for mapping a Domain Name to an IPv4 address
|AAAA Record (pronounced "quad-A")
||IPv6 Host Record, used for mapping a Domain Name to an IPv6 address
|CNAME Record (Canonical Names)
||Alias Record, used for mapping an alias of a DNS domain name. CNAME Record are useful to use more than one name to a single host. CNAME Records allow using different names for same host.
||Mail Exchanger, used for mapping a DNS domain name to the mail server. MX (Mail Exchanger) Records are used by e-mail applications to locate mail server for a DNS domain, based on the destination e-mail address. MX (Mail Exchanger) Record stores the mail server information for a particular domain.
|| Pointer, used for reverse lookup (IP Address to Domain Name resolution)
|| SRV record, used to map available services. Mainly used by Active Directory in Microsoft Windows Servers