Internet Protocol version 4 (IPv4) is a communication protocol used for transmitting data over the Internet. It defines how devices on a network identify and locate each other using unique numerical addresses, known as IP addresses. Each IPv4 address consists of four sets of numbers, ranging from 0 to 255, separated by periods, such as 192.168.1.1. IPv4 supports approximately 4.3 billion unique addresses, which was sufficient in the early days of the Internet. However, with the rapid growth of connected devices, the available addresses are nearly exhausted, leading to the development of Internet Protocol version 6 (IPv6) to accommodate the increasing demand.