AAAA is a domain name record, that's basically the IPv6 address of the server where the domain name is hosted. The IPv6 system was designed to replace the current IPv4 system in which each and every IP address is made up of 4 sets of decimal numbers ranging from 1 to 255 e.g. 220.127.116.11. However, an IPv6 address features 8 sets of 4 hexadecimal numbers - which range from 0 to 9 and from A to F. The cause of this transformation is the considerably smaller selection of unique IPs which the present system supports as well as the quick increase of devices that are connected to the world wide web. A good example of an IPv6 address is 2101:1f34:32e2:2415:1365:4f2b:2553:1345. If you wish to forward a domain address to a server which uses this kind of an address, you will have to set up an AAAA record for it, and not the widespread A record, which is an IPv4 address. Both records have the exact same function, but different notations are used, so as to separate the two sorts of addresses.