The purpose of a network topology in computer networking is to define the arrangement and interconnection of nodes within a network. Common topologies include star, ring, bus, and mesh, each with its own advantages and disadvantages. Understanding network topology is crucial for optimizing performance, ensuring data flow efficiency, and facilitating troubleshooting. For instance, a star topology allows for easy addition or removal of nodes with minimal network disruption. By clearly outlining how different devices connect and communicate, network topology plays a foundational role in effective network design and management.