AAAA is a domain 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 present IPv4 system in which every single IP address is made up of four sets of decimal digits ranging from 1 to 255 e.g. 126.96.36.199. However, an IPv6 address includes eight sets of 4 hexadecimal numbers - which range from 0 to 9 and from A to F. The main reason for this modification is the considerably smaller selection of unique IPs which the existing system supports as well as the rapid increase of gadgets that are connected to the world wide web. An illustration of an IPv6 address would be 2101:1f34:32e2:2415:1365:4f2b:2553:1345. If you wish to direct a domain to a machine that uses such an address, you will have to create an AAAA record for it, and not the widely used A record, which is an IPv4 address. The two records provide the exact same function, yet different notations are used, to separate the two forms of addresses.