IPv4, or Internet Protocol version 4, is the fourth version of the Internet Protocol, which is the principal set of rules for communication over the Internet or on a local network. It uses 32-bit addresses, typically expressed in dotted decimal notation, to uniquely identify network interfaces on machines.
An IPv4 address is divided into two primary parts: the network part, which specifies the unique number assigned to the network, and the host part, which uniquely identifies a machine on the network.
IPv4 addresses are limited to approximately 4.3 billion unique addresses, which has led to address exhaustion. As a result, the Internet is gradually transitioning to IPv6, which offers a vastly larger address space. Some advantages of IPv4 include its widespread support on network devices, simple topology, and compatibility with millions of devices. However, it also has limitations such as address exhaustion, inefficient internet routing, and high system management costs.