Overview

This article explains the different types of records that a domain can have and what they are used for. The DNS tab on the  Manage Websites page is where you’ll locate your Mail DNS entries. For further information, see the Adding DNS article.

Wikipedia also has a list of DNS record types.

A
The “Address” record (A record) is used to map the hostname to an IPv4 address.
a track record
AAAA
This is a record for IPv6 addresses. This can be used to forward the host name mapping to an IPv6 address.
IPv6 AAAA record
ALIAS
An ALIAS record is a virtual DNS record that works similarly to a CNAME but can be added to the root domain name (which is not possible with a CNAME). It can also be added to an existing subdomain record where a CNAME must be unique.
A record of aliases
CAAA Certification Authority Authorization (CAA) record specifies which certificate authorities (CA) are permitted to issue certificates for a certain domain name.
CNAME
The CNAME record, or “canonical name record,” links one domain name to another.
A CNAME record is a name that is assigned to a
MX
Also called as “mail exchange” records, these records display the host record for mail hosting that the domain is pointing to.
For Internet telephony, MX records and NAPTR Name Authority Pointer (NAPTR) records are most commonly utilized.
NS

Nameserver records delegate a domain or subdomain to a DNS server via the NAPTR record.
Nameservers \sPTR
Also known as a “pointer record.” This is used to map an IP address to a hostname in reverse. When a Unique IP is added to a domain, GreggHost presently only supports reverse DNS records.
Note: On shared email hosting, a Unique IP address cannot be utilized to remedy mail-blocking difficulties.

More information on Unique IPs can be found here:
IP address that is unique
PTR records are also supported by DreamCompute, but in order for the records to be created automatically, you must first configure DNS for your domain(s). Please contact support if the PTR record does not appear to be right within 15 minutes after making this adjustment.
SPF
records determine which mail servers are allowed to send email from your domain.
SRV 

“Service locator” records in the SPF record advertise a specific service that a server provides.
TXT
Txt records are text strings that are free-form. They’re useful for things like Google verification records and DKIM email signatures.
TXT files are text files.
In the following article, you may learn more about IP addresses and the two types that are commonly used:

Additional details

Additional details

Additional information on other DNS records or terminologies can be found below:

DNS A record lookup

When looking for an A record, you could get a CNAME record back, such as:
[server]
$ excavating www.cloudflare.com
www.cloudflare.com. IN CNAME 260
www.cloudflare.com.cdn.cloudflare.net. \swww.cloudflare.com.cdn.cloudflare.net. www.cloudflare.com.cdn.cloudflare.net 260 IN A 198.41.215.163 A 198.41.214.163 IN A
You can search up the CNAME record’s A record. Either another CNAME record or an A record will be offered to you.
Domain name that is fully qualified
A FQDN is a one-of-a-kind domain that cannot be mistaken with other domains. If your website is example.com, you may have many FQDNs.

www.example.com
For more details, see the following article:

Zone file with fully qualified domain names
A zone file is a text record that maps your domain and subdomain names to their IP addresses. For more details, see the following article:

the zone file
GreggHost does not provide a service to export the Zone file for your domain. You must copy your DNS records from your panel if you need a list of the domain’s records.

Record of SOA
The first resource record in a DNS Zone file is the Start of Authority record. The following authoritative information about a domain is specified in the SOA record:

The SOA record was produced on the primary name server.
Email address for the Zone file’s administrator. (Instead of the @ symbol, a period is used.)
The serial number of the domain. This is the Zone file’s revision number.
Timers:
Time for a refresh
Time to try again
Time to expire
TTL Minimum
To look for a SOA record, use SSH and use the command below. This example performs a search on dreamhost.com:

$ nslookup -type=soa dreamhost.com [server]

64.90.63.202 is the IP address of the server.
64.90.63.202#53 is the IP address of the server. dreamhost.com origin = ns1.dreamhost.com is a non-authoritative response. hostmaster.dreamhost.com mail addr refresh = 14534 serial = 2015091000 1800 retries 1814400 is the expiration date. 14400 as a minimum