Every single device that's connected to the Internet has a unique identifier called IP (Internet Protocol) address. This includes computers, web servers, smartphones, switches, and so on. The pool of addresses, that was introduced initially, has already been distributed, therefore the so-called IPv4 IP addresses are gradually being replaced with IPv6 addresses. Every domain which opens a website has an IP record, that is the address of the server where it's hosted. Using the IPv4 system, the record is called A and it consists of 4 groups of numbers from 1 to 255 divided with a dot, while within the IPv6 system it is called AAAA and it is comprised of eight sets 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 is designed for a considerably bigger amount of IPs than the IPv4 format.