Every single device that is connected to the web has a distinctive identifier known as IP (Internet Protocol) address. This includes personal computers, web servers, smartphones, switches, etcetera. The pool of IPs, that was introduced at first, is already distributed, so the so-called IPv4 IP addresses are gradually being replaced with IPv6 addresses. Every domain that opens an internet site has an IP record, that is the address of the server where it is hosted. With the IPv4 system, the record is called A and it comprises of 4 sets of numbers from 1 to 255 split up by a dot, while in the IPv6 system it's called AAAA and it is made up of eight 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 works with a substantially larger amount of IPs in comparison with the IPv4 format.