Every device that is connected to the Internet has a unique identifier known as IP (Internet Protocol) address. This includes personal computers, web servers, smartphones, switches, etc. The pool of IP addresses, which was introduced originally, has been distributed, so the so-called IPv4 IP addresses are slowly being replaced with IPv6 addresses. Every domain that opens an internet site comes with an IP record, that is the address of the server where it is hosted. When using the IPv4 system, the record is called A and it consists of 4 sets of numbers from 1 to 255 separated with a dot, while with the IPv6 system it's called AAAA and it is made up of 8 groups of hexadecimal numbers i.e. this type of records use digits from 0 to 9 and letters from A to F. An example of an AAAA record is 2010:0c48:43d3:2142:1012:8c3a:2475:2435 and this format works with a significantly larger amount of IPs than the IPv4 format.