Each device which is connected to the web has a distinctive identifier named IP (Internet Protocol) address. This includes computers, web servers, smart phones, switches, etcetera. The pool of IPs, which was introduced originally, has already been distributed, hence 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. When using the IPv4 system, the record is called A and it comprises of 4 sets of numbers from 1 to 255 split up using a dot, while in the IPv6 system it's called AAAA and it consists of eight groups of hexadecimal numbers i.e. this type of records use digits 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 substantially bigger amount of IPs when compared with the IPv4 format.