Each device that's connected to the Internet has a unique identifier called IP (Internet Protocol) address. This includes personal computers, web servers, smartphones, switches, etc. The pool of IPs, which was introduced initially, is already distributed, so the so-called IPv4 IP addresses are slowly being replaced with IPv6 addresses. Every domain name that opens a site comes with an IP record, that is the address of the server where it is hosted. When using the IPv4 system, the record is called A and it is comprised of 4 groups of numbers from 1 to 255 split up using a dot, while within the IPv6 system it's called AAAA and it is comprised of eight groups of hexadecimal numbers i.e. this sort of records use digits from 0 to 9 and letters from A to F. An illustration of an AAAA record is 2010:0c48:43d3:2142:1012:8c3a:2475:2435 and this format works with a substantially larger amount of IPs in comparison with the IPv4 format.