Network theory is a branch of mathematics and computer science that studies the relationships and connections between various entities, often represented as graphs. In this context, nodes represent the entities, while edges symbolize the connections between them. This framework helps analyze complex systems, such as social networks, transportation systems, and biological networks. By examining how nodes interact, network theory can reveal patterns and behaviors within these systems. For example, it can identify influential nodes in a social network or optimize routes in a transportation network. Overall, network theory provides valuable insights into the structure and dynamics of interconnected systems.