AAAA is a domain address record, that's in essence the IPv6 address of the web server in which the domain is hosted. The IPv6 system was introduced to replace the current IPv4 system in which each and every IP address comprises of 4 groups of decimal digits between 1 to 255 e.g. 126.96.36.199. On the other hand, an IPv6 address includes 8 groups of 4 hexadecimal digits - which range from 0 to 9 and from A to F. The cause of this transformation is the significantly smaller amount of unique IPs the existing system supports as well as the fast increase of gadgets 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 direct a domain address to a web server which uses this sort of an address, you will need to create an AAAA record for it, and not the commonly used A record, which is an IPv4 address. The two records have the exact same function, yet different notations are used, in order to identify the two types of addresses.