AAAA is a domain name record, which is basically the IPv6 address of the server where the domain is hosted. The IPv6 system was designed to replace the present IPv4 system where every single Internet protocol address consists of 4 sets of decimal digits ranging from 1 to 255 e.g. 22.214.171.124. In contrast, an IPv6 address includes eight sets of four hexadecimal digits - from 0 to 9 and from A to F. The main reason for this change is the significantly smaller amount of unique IPs that the existing system supports and also the speedy increase of devices 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 want to point a domain address to a machine that uses such an address, you need to create an AAAA record for it, not the widespread A record, which is an IPv4 address. Both records have the very same function, yet different notations are used, in order to separate the two types of addresses.