Every single device that's connected to the web has a distinctive identifier referred to as IP (Internet Protocol) address. This includes computers, web servers, smart phones, switches, etc. The pool of addresses, that was introduced initially, has been distributed, hence the so-called IPv4 IP addresses are progressively being replaced with IPv6 addresses. Every domain that opens a website comes with 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 comprises of four sets of numbers from 1 to 255 divided with a dot, while with the IPv6 system it is called AAAA and it comprises of 8 sets of hexadecimal numbers i.e. this kind of records use digits 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 supports a considerably larger amount of IPs than the IPv4 format.