Each device that is connected to the web has a distinctive identifier called IP (Internet Protocol) address. This includes computers, web servers, smartphones, switches, etc. The pool of IP addresses, that was introduced at first, has been distributed, therefore the so-called IPv4 IP addresses are gradually being replaced with IPv6 addresses. Every domain name which opens a website comes with an IP record, that is the address of the server where it's hosted. With the IPv4 system, the record is called A and it is comprised of 4 sets of numbers from 1 to 255 divided with a dot, while with the IPv6 system it's called AAAA and it comprises of eight 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 can handle a significantly bigger number of IPs in comparison with the IPv4 format.