An AAAA record is an IP within the recently introduced IPv6 format and it is comprised of eight different sets of hexadecimal numbers, unlike the IPv4 IPs, which include 4 sets of digits in between 1 and 255. An example of an IPv6 address would be 3014:0d43:23a3:2354:1320:8f3b:2635:3254 and in this format the amount of IPs that could be created is many times larger than the number of the IPv4 addresses. Each domain has its website hosting server IP address as a record and in essence, that record tells the domain address where the website for it is. Depending on the system which the service provider employs, the record will be called A (IPv4) or AAAA (IPv6). Changing this record allows you to host your site with one company and your emails with another, so if you choose to use such a redirection to forward a domain name to a server that uses an IPv6 address, you'll need to create an AAAA record for it.