Every device that's connected to the Internet has a distinctive identifier named IP (Internet Protocol) address. This includes computer systems, web servers, smart phones, switches, etc. The pool of addresses, which was introduced originally, is already distributed, so the so-called IPv4 IP addresses are gradually being replaced with IPv6 addresses. Every domain that opens a site comes with 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 is comprised of four sets of numbers from 1 to 255 split up by a dot, while with the IPv6 system it's called AAAA and it is made up of eight sets of hexadecimal numbers i.e. this sort of records use numbers 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 considerably greater amount of IPs when compared with the IPv4 format.