SRV : Service locator (RFC 2782)
Generalized service location record, used for newer protocols instead of creating protocol-specific records such as MX.

NSEC3 : NSEC record version 3 (RFC 5155)
An extension to DNSSEC that allows proof of nonexistence for a name without permitting zonewalking

AXFR : Full Zone Transfer (RFC 1035)
Transfer entire zone file from the master name server to secondary name servers.

AAAA : IPv6 address record (RFC 3596)
Returns a 128-bit IPv6 address, most commonly used to map hostnames to an IP address of the host.

SIG : Signature (RFC 2535)
Signature record used in SIG(0) (RFC 2931). Until RFC 3755 was published, the SIG record was part of DNSSEC; now RRSIG is used for that.

DNAME : delegation name (RFC 2672)
DNAME will delegate an entire portion of the DNS tree under a new name. In contrast, the CNAME record creates an alias of a single name. Like the CNAME record, the DNS lookup will continue by retrying the lookup with the new name.

TSIG : Transaction Signature (RFC 2845)
Record that supports one set of security mechanisms for DNS. Used to secure communication between DNS resolvers and Name servers, in contrast to DNSSEC, which secures the actual DNS records from the authoritative name server.

DLV : DNSSEC Lookaside Validation record (RFC 4431)
For publishing DNSSEC trust anchors outside of the DNS delegation chain. Uses the same format as the DS record. RFC 5074 describes a way of using these records.

DHCID : DHCP identifier (RFC 4701)
Used in conjunction with the FQDN option to DHCP

CNAME : Canonical name record (RFC 1035)
Alias of one name to another: the DNS lookup will continue by retrying the lookup with the new name.

DNSKEY : DNS Key record (RFC 4034)
The key record used in DNSSEC. Uses the same format as the KEY record.

OPT : Option (RFC 2671)
This is a 'pseudo DNS record type' needed to support EDNS

KEY : Key record (RFC 4034)
Used only for TKEY (RFC 2930). Before RFC 3755 was published, this was also used for DNSSEC, but DNSSEC now uses DNSKEY.

LOC : Location record (RFC 1876)
Specifies a geographical location associated with a domain name

TA : DNSSEC Trust Authorities (None)
Part of a deployment proposal for DNSSEC without a signed DNS root. See the IANA database and Weiler Spec] for details. Uses the same format as the DS record.

CERT : Certificate record (RFC 4398)
Stores PKIX, SPKI, PGP, etc.

NAPTR : Naming Authority Pointer (RFC 3403)
Allows regular expression based rewriting of domain names which can then be used as URIs, further domain names to lookups, etc.

HIP : Host Identity Protocol (RFC 5205)
Method of separating the end-point identifier and locator roles of IP addresses.