AAAA is a domain address record, which is in essence the IPv6 address of the web server in which the domain is hosted. The IPv6 system was designed to replace the existing IPv4 system where each IP address comprises of 4 sets of decimal numbers which range from 1 to 255 e.g. 126.96.36.199. However, an IPv6 address includes eight sets of 4 hexadecimal numbers - from 0 to 9 and from A to F. The cause of this transformation is the substantially smaller amount of unique IPs that the current system supports and also the speedy increase of gadgets that are connected to the world wide web. A good example of an IPv6 address would be 2101:1f34:32e2:2415:1365:4f2b:2553:1345. If you need to forward a domain to a web server that uses such an address, you will need to create an AAAA record for it, and not the widespread A record, that is an IPv4 address. The 2 records have the very same function, yet different notations are used, in order to separate the two types of addresses.