AAAA is a domain name record, which is basically the IPv6 address of the server where the domain is hosted. The IPv6 system was introduced to replace the present IPv4 system where each and every IP address is comprised of four sets of decimal digits between 1 to 255 e.g. 5.168.208.143. In contrast, an IPv6 address includes 8 sets of 4 hexadecimal digits - from 0 to 9 and from A to F. The reason behind this transformation is the significantly smaller number of unique IPs which the current system supports as well as the speedy increase of units that are connected to the Internet. An illustration of an IPv6 address would be 2101:1f34:32e2:2415:1365:4f2b:2553:1345. If you need to forward a domain name to a machine that uses this kind of an address, you will have to create an AAAA record for it, not the widely used A record, that is an IPv4 address. The two records provide the very same function, yet different notations are used, so as to separate the two forms of addresses.