Each device which is connected to the world wide web has a distinctive identifier known as IP (Internet Protocol) address. This includes computer systems, web servers, smart phones, switches, and so on. The pool of IPs, which was introduced initially, is already distributed, so the so-called IPv4 IP addresses are gradually getting replaced with IPv6 addresses. Every domain name which opens an internet site comes with 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 four groups of numbers from 1 to 255 split up by a dot, while in the IPv6 system it is called AAAA and it consists of eight sets 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 considerably bigger number of IPs when compared with the IPv4 format.