Every single device that's connected to the world wide web has a distinctive identifier called IP (Internet Protocol) address. This includes personal computers, web servers, smart phones, switches, etc. The pool of IPs, that was introduced initially, has already been distributed, hence the so-called IPv4 IP addresses are gradually getting replaced with IPv6 addresses. Every domain name which opens a website has an IP record, that is the address of the server where it's hosted. When using the IPv4 system, the record is called A and it is made up of 4 sets of numbers from 1 to 255 separated with a dot, while within the IPv6 system it's called AAAA and it comprises of eight sets of hexadecimal numbers i.e. this type 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 can handle a considerably bigger amount of IPs than the IPv4 format.