Each device that's connected to the world wide web has a specific identifier named IP (Internet Protocol) address. This includes computers, web servers, smartphones, switches, and so on. The pool of IPs, which was introduced at first, is already distributed, hence the so-called IPv4 IP addresses are progressively being replaced with IPv6 addresses. Every domain which opens a website has an IP record, that is the address of the server where it is hosted. With the IPv4 system, the record is called A and it consists of 4 sets of numbers from 1 to 255 divided with a dot, while with the IPv6 system it's called AAAA and it is comprised of eight groups of hexadecimal numbers i.e. this kind 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 can handle a substantially bigger amount of IPs than the IPv4 format.