Mininet is a network emulator that allows users to create and test virtual networks on a single machine. It simulates a complete network stack, including hosts, switches, and links, enabling developers to experiment with network configurations and protocols without needing physical hardware. This tool is widely used in research and education to facilitate the study of software-defined networking (SDN) and network functions virtualization (NFV). By providing a lightweight and flexible environment, Mininet helps users quickly prototype and evaluate networking concepts, making it an essential resource for network engineers and students alike.