Every device that is connected to the web has a special identifier known as IP (Internet Protocol) address. This includes computer systems, web servers, smartphones, switches, etc. The pool of addresses, which was introduced at first, has already been distributed, therefore the so-called IPv4 IP addresses are steadily getting replaced with IPv6 addresses. Every domain name that opens a site has an IP record, which is the address of the server where it is hosted. Using the IPv4 system, the record is called A and it comprises of 4 sets of numbers from 1 to 255 separated by a dot, while with the IPv6 system it's called AAAA and it consists of eight groups of hexadecimal numbers i.e. this sort 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 significantly bigger number of IPs compared with the IPv4 format.