Network models, as a technique, represent systems as graphs comprising nodes (entities) and edges (interactions), enabling formal analysis of structural and dynamical properties. They are used to encode dependencies, flows, or relational patterns in domains such as communication, transportation, biology, and social systems. Techniques include constructing adjacency or incidence matrices, selecting appropriate network types (e.g., directed, weighted, multilayer), and applying algorithms for community detection, centrality analysis, path optimization, and robustness assessment. Network models support simulation of processes on networks (e.g., diffusion, contagion, routing) and provide a framework for quantitative inference, prediction, and optimization based on the topology and edge attributes.