You have just completed the chapter related to one of the most important data structures available while developing applications, namely graphs. As you have learnt, a graph is a data structure that consists of nodes and edges. Each edge connects two nodes. What is more, there are various variants of edges in a graph, such as undirected and directed, as well as unweighted and weighted. All of them have been described and explained in detail, together with diagrams and code samples. Two methods of graph representation, namely using an adjacency list and an adjacency matrix, have been explained as well. Of course, you have also learnt how to implement a graph using the C# language.

While talking about graphs, is also important to present some real-world applications, especially due to the common use of such a data structure. For example, the chapter contains the description of the structure of friends available in social media or the problem of searching for the shortest path in a city...