Every single device that's connected to the Internet has a special identifier known as IP (Internet Protocol) address. This includes computer systems, web servers, smart phones, switches, and so on. The pool of addresses, which was introduced at first, is already distributed, therefore the so-called IPv4 IP addresses are gradually being replaced with IPv6 addresses. Every domain that opens a site has an IP record, which is the address of the server where it's hosted. With the IPv4 system, the record is called A and it consists of 4 groups of numbers from 1 to 255 divided with a dot, while within the IPv6 system it is called AAAA and it consists of eight sets of hexadecimal numbers i.e. this type of records use numbers 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 is designed for a substantially greater amount of IPs in comparison with the IPv4 format.