AAAA is a domain name record, that's essentially the IPv6 address of the web server where the domain name is hosted. The IPv6 system was designed to replace the current IPv4 system where every single IP address is comprised of 4 sets of decimal numbers between 1 to 255 e.g. 126.96.36.199. However, an IPv6 address includes 8 groups of four hexadecimal digits - which range from 0 to 9 and from A to F. The main reason for this modification is the tremendously smaller amount of unique IPs which the current system supports as well as the quick increase of gadgets that are connected to the world wide web. An illustration of an IPv6 address is 2101:1f34:32e2:2415:1365:4f2b:2553:1345. If you need to forward a domain name to a machine which uses this kind of an address, you have to set up an AAAA record for it, and not the commonly used A record, that is an IPv4 address. The two records deliver the very same function, yet different notations are used, to identify the two sorts of addresses.