Each 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, and so on. The pool of addresses, which was introduced originally, is already distributed, so the so-called IPv4 IP addresses are slowly getting replaced with IPv6 addresses. Every domain name that opens an internet site comes with an IP record, which is the address of the server where it is hosted. With the IPv4 system, the record is called A and it comprises of 4 groups of numbers from 1 to 255 split up by a dot, while in the IPv6 system it is called AAAA and it is made up of 8 groups of hexadecimal numbers i.e. this kind 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 can handle a considerably greater number of IPs compared with the IPv4 format.