Visually Explained Algorithms The adjacency matrix is a square matrix that’s used to represent a graph. The elements that are next to each other represent adjacent vertices. Why would you want to create an adjacency matrix? To save time. The adjacency matrix is much more efficient when trying to figure out the adjacent nodes in a graph. Let’s look at an example of how someone would create an adjacency matrix from a directed graph. Although the graph looks complicated, creating an adjacency matrix is a simple process. Since there are 6 vertices, the adjacency matrix will have 6 rows and