Graph-based models are mathematical structures used to represent relationships between objects. In these models, objects are represented as nodes (or vertices), while the connections between them are represented as edges. This framework allows for the analysis of complex networks, such as social networks, transportation systems, and biological pathways. These models are particularly useful in various fields, including computer science, biology, and social sciences. They enable researchers to visualize and analyze data, uncover patterns, and make predictions. Popular algorithms, such as Dijkstra's algorithm and PageRank, are often applied to graph-based models to solve problems related to shortest paths and ranking.