Description: The path length in graph theory refers to the number of edges that make up a path connecting two vertices in a graph. A path is a sequence of vertices where each pair of consecutive vertices is connected by an edge. The length of a path is a fundamental concept that allows measuring the distance between two points in a graph, making it essential for various applications in mathematics, computer science, and related fields. In an undirected graph, the path length is simply counted by summing the edges traversed, while in a directed graph, the direction of the edges must be considered. This concept applies not only to simple graphs but also to more complex structures such as weighted graphs, where each edge may have an associated weight or cost, allowing for more meaningful distance calculations. Path length is crucial in search and optimization algorithms, such as Dijkstra’s algorithm, which is used to find the shortest path between two vertices in a weighted graph. In summary, path length is a key concept in graph theory that facilitates the analysis and resolution of problems related to connectivity and distance in networks.