Each device which is connected to the world wide web has a unique identifier referred to as IP (Internet Protocol) address. This includes PCs, web servers, smartphones, switches, etcetera. The pool of IP addresses, that was introduced originally, is already distributed, therefore the so-called IPv4 IP addresses are gradually being replaced with IPv6 addresses. Every domain which opens a site has 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 consists of 4 sets of numbers from 1 to 255 divided using a dot, while in the IPv6 system it is called AAAA and it consists 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 is designed for a significantly bigger amount of IPs compared with the IPv4 format.
