Each device that's connected to the Internet has a specific identifier called IP (Internet Protocol) address. This includes computer systems, web servers, smartphones, switches, etcetera. The pool of IPs, that was introduced at first, has already been distributed, hence the so-called IPv4 IP addresses are steadily getting replaced with IPv6 addresses. Every domain which opens a site comes with an IP record, which is the address of the server where it is hosted. With the IPv4 system, the record is called A and it comprises of four sets of numbers from 1 to 255 split up with a dot, while in the IPv6 system it's called AAAA and it consists of 8 groups of hexadecimal numbers i.e. this type 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 works with a significantly greater amount of IPs in comparison with the IPv4 format.