An IP address, or Internet Protocol Address is the unique number given to every computer connected to the Internet. This number allows users and other computers to find each other.
In the IPv4 scheme, IP addresses consist of 4 bytes, allowing for a full range of 4,294,967,295 unique addresses. Represented visually these addresses consist of four numbers which are between 0 and 255, separated by periods, such as 18.104.22.168.
In IPv6, IP addresses consist of 16 bytes, allowing for a theoretically total of 340,282,366,920,938,463,463,374,607,431,768,211,456 unique addresses. The literal representation is done in blocks of 16 bits written in hex, separated by colon, such as 2001:db8:1:2:3:4:5:6 (zeros at the left don't need to be written). A longer address, with many zeros can get compressed; for example ff02:0:0:0:0:0:0:1 will become ff02::1.