Every single device that is connected to the world wide web has a distinctive identifier called IP (Internet Protocol) address. This includes PCs, web servers, smart phones, switches, and so on. The pool of addresses, which was introduced originally, is already distributed, hence the so-called IPv4 IP addresses are slowly getting replaced with IPv6 addresses. Every domain that opens an internet site has an IP record, that is the address of the server where it's hosted. With the IPv4 system, the record is called A and it comprises of 4 groups of numbers from 1 to 255 separated with a dot, while in the IPv6 system it is called AAAA and it is comprised of eight groups of hexadecimal numbers i.e. this type of records use numbers from 0 to 9 and letters from A to F. An illustration of an AAAA record is 2010:0c48:43d3:2142:1012:8c3a:2475:2435 and this format works with a substantially larger amount of IPs when compared with the IPv4 format.