Each device that is connected to the world wide web has a unique identifier referred to as IP (Internet Protocol) address. This includes personal computers, web servers, smart phones, switches, and so on. The pool of IPs, that was introduced originally, has been distributed, hence the so-called IPv4 IP addresses are slowly getting replaced with IPv6 addresses. Every domain name that opens a site has an IP record, which is the address of the server where it's hosted. Using the IPv4 system, the record is called A and it consists of 4 sets of numbers from 1 to 255 separated with a dot, while with the IPv6 system it's called AAAA and it comprises of 8 sets of hexadecimal numbers i.e. this kind 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 supports a significantly bigger amount of IPs when compared with the IPv4 format.