AAAA is a domain name record, that is essentially the IPv6 address of the web server where the domain is hosted. The IPv6 system was introduced to replace the existing IPv4 system where each and every IP address comprises of four groups of decimal digits between 1 to 255 e.g. 18.104.22.168. In comparison, an IPv6 address has 8 groups of four hexadecimal digits - which range from 0 to 9 and from A to F. The reason behind this modification is the substantially smaller amount of unique IPs the present system supports and the speedy increase of units 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 wish to direct a domain to a server that uses this type of an address, you have to set up an AAAA record for it, not the widespread A record, that is an IPv4 address. Both records deliver the same exact function, but different notations are used, in order to identify the two types of addresses.