Internet Protocol version 4 (IPv4) is a technical standard used to define a single unique IP address on a network. An IPv4 address is expressed as four numbers separated by periods.
For example: 126.96.36.199.
With the rapid growth of the Internet, it was evident that many more IP addresses than what the IPv4 protocol could provide would be needed. In response, the Internet Engineering Task Force (IETF) developed Internet Protocol version 6 (IPv6) which greatly expanded the number of IP addresses available.