Protocol Independent Multicast (PIM) is a routing protocol used to manage multicast traffic in networks. It allows the efficient distribution of data to multiple recipients without needing a specific underlying unicast protocol. PIM operates in two main modes: Sparse Mode and Dense Mode, which cater to different network conditions and requirements. In Sparse Mode, multicast groups are created only when there are active receivers, minimizing unnecessary traffic. Conversely, Dense Mode assumes that receivers are present in most parts of the network, flooding the traffic initially and then pruning back where there are no receivers. This flexibility makes PIM suitable for various network environments.