Every device that is connected to the web has a specific identifier called IP (Internet Protocol) address. This includes PCs, web servers, smart phones, switches, etc. The pool of addresses, that was introduced originally, has already been distributed, therefore the so-called IPv4 IP addresses are progressively getting replaced with IPv6 addresses. Every domain that 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 comprised of four sets of numbers from 1 to 255 split up using a dot, while within the IPv6 system it's called AAAA and it comprises of eight sets of hexadecimal numbers i.e. this sort 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 greater number of IPs when compared with the IPv4 format.