Type A and AAAA records require that the Address field be an IP address. Types CNAME, MX, NS, and PTR require a domain name in the Address field.

If the domain name is not fully qualified (ending with '.'), it will be qualified by appending the Zone name:

'www' => 'www.myzone.com.' Some characters have special meaning and use:
CharacterMeaningExample
@ The @ character can be used to stand for the name of the parent zone. @ (becomes zone.com.)
www.@ (becomes www.zone.com.)
* You can use the * character only at the beginning of the Address *.zone.com.
*
/ You can use the / character only in Reverse Lookup Addresses that end with '.in-addr.arpa.' 1.0/24.3.4.5.in-addr.arpa.
1.2.0/16.3.4.in-addr.arpa.
& Addresses that end in .& will have the & character changed to 'in-addr.arpa.' 1.2.3.4.& (becomes 1.2.3.4.in-addr.arpa. )
1.2.0/16.3.4.& (becomes 1.2.0/16/3.4.in-addr.arpa. )