IPv4 Addressing is a method used to identify devices on a network through unique numerical labels. An IPv4 address consists of four sets of numbers, each ranging from 0 to 255, separated by periods (e.g., 192.168.1.1). This format allows for approximately 4.3 billion unique addresses, which are essential for routing data across the internet. Each IPv4 address is divided into two main parts: the network portion and the host portion. The network portion identifies the specific network, while the host portion identifies the individual device within that network. This structure helps manage and organize the vast number of devices connected to the internet.