Each device which is connected to the web has a specific identifier called IP (Internet Protocol) address. This includes computer systems, web servers, smartphones, switches, and so on. The pool of addresses, which was introduced originally, has already been distributed, so the so-called IPv4 IP addresses are slowly being replaced with IPv6 addresses. Every domain name that opens an internet site has an IP record, that is the address of the server where it's hosted. Using the IPv4 system, the record is called A and it comprises of four groups of numbers from 1 to 255 separated using a dot, while within the IPv6 system it's called AAAA and it consists of eight groups of hexadecimal numbers i.e. this sort 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 supports a significantly greater amount of IPs when compared with the IPv4 format.