Every device that's connected to the web has a specific identifier called IP (Internet Protocol) address. This includes computers, web servers, smart phones, switches, etcetera. The pool of IPs, which was introduced at first, is already distributed, so the so-called IPv4 IP addresses are gradually getting replaced with IPv6 addresses. Every domain name which opens a website has an IP record, which is the address of the server where it is hosted. Using the IPv4 system, the record is called A and it comprises of four groups of numbers from 1 to 255 split up with a dot, while in the IPv6 system it is called AAAA and it is comprised of 8 groups of hexadecimal numbers i.e. this sort of records use digits from 0 to 9 and letters from A to F. A good example of an AAAA record is 2010:0c48:43d3:2142:1012:8c3a:2475:2435 and this format is designed for a substantially bigger number of IPs compared with the IPv4 format.