AAAA is a domain address record, that's essentially the IPv6 address of the server where the domain is hosted. The IPv6 system was designed to replace the present IPv4 system where every single Internet protocol address is made up of 4 groups of decimal numbers between 1 to 255 e.g. 5.168.208.143. In comparison, an IPv6 address includes 8 sets of 4 hexadecimal numbers - from 0 to 9 and from A to F. The reason for this modification is the significantly smaller number of unique IPs that the existing system supports and also 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 wish to point a domain to a web server that uses such an address, you'll have to set up an AAAA record for it, and not the widely used A record, which is an IPv4 address. The two records deliver the very same function, but different notations are used, in order to distinguish the two types of addresses.