AAAA is a domain record, that's basically the IPv6 address of the server in which the domain name is hosted. The IPv6 system was intended to replace the current IPv4 system in which each IP address consists of 4 sets of decimal digits ranging from 1 to 255 e.g. 126.96.36.199. In comparison, an IPv6 address includes 8 sets of 4 hexadecimal digits - which range from 0 to 9 and from A to F. The reason for this modification is the substantially smaller range of unique IPs which the current system supports and the quick increase of products which are connected to the world wide web. An example of an IPv6 address would be 2101:1f34:32e2:2415:1365:4f2b:2553:1345. If you want to point a domain to a server which uses such an address, you will need to set up an AAAA record for it, and not the widespread A record, which is an IPv4 address. Both records deliver the very same function, but different notations are used, to identify the two sorts of addresses.