A Records are used to point a logical domain name, such as "google.com", to the IP address of Google's hosting server, "74.125.224.147".
Provides the ability to associate some arbirary and unformatted text with a host or other name. The TXT record is used to define the Sender Policy Framework and DomainKeys Signed Mail.
A mail exchanger record (MX record) is a type of resource record in the Domain Name System that specifies a mail server responsible for accepting email messages on behalf of a recipient's domain.
Name server (NS) records determine which servers will communicate DNS information for a domain. Generally, you will have primary and secondary name server records for your domain.
A CNAME record is an abbreviation for Canonical Name record and is a type of resource record in the Domain Name System that specifies that the domain name is an alias of another, canonical domain name.
Service record (SRV record) is a specification of data in the Domain Name System defining the location, i.e. the hostname and port number, of servers for specified services.