AAAA is a domain address record, which is basically the IPv6 address of the web server in which the domain is hosted. The IPv6 system was intended to replace the current IPv4 system where each Internet protocol address is made up of four sets of decimal digits which range from 1 to 255 e.g. 22.214.171.124. However, an IPv6 address has 8 groups of 4 hexadecimal digits - ranging from 0 to 9 and from A to F. The reason for this transformation is the considerably smaller number of unique IPs that the existing system supports as well as the quick increase of products that are connected to the Internet. A good example of an IPv6 address is 2101:1f34:32e2:2415:1365:4f2b:2553:1345. If you want to direct a domain to a web server which uses this sort of an address, you'll have to set up an AAAA record for it, not the widespread A record, which is an IPv4 address. The two records provide the exact same function, yet different notations are used, so as to differentiate the two sorts of addresses.