Each device which is connected to the web has a special identifier called IP (Internet Protocol) address. This includes computers, web servers, smart phones, switches, and so on. The pool of IPs, that was introduced originally, has been distributed, therefore the so-called IPv4 IP addresses are progressively being replaced with IPv6 addresses. Every domain name which opens a website 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 made up of four sets of numbers from 1 to 255 divided by a dot, while within the IPv6 system it is called AAAA and it is made up of 8 sets of hexadecimal numbers i.e. this kind 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 considerably larger amount of IPs than the IPv4 format.