DNS Record Types:-
A - Returns a 32-bit IPv4 address and its this is used more frequestly
AAAA - Returns a 128-bit IPv6 address
CNAME - Alias is a name of other name, ie mail.domain.com ref to smtp.domain.com
MX - this is mainly used by mail daemons, this record used to lookup mail server information for a domain and can send a mail to it.
PTR - This is an reverse DNS Lookup
SOA - This holds Authoritative information
SRV - This will return lookup based on protocol
TXT - returns human readable text information, this is being used to store hardware information for the host.
AXFR - This is userd for transfering record between master and slave servers.