Graph

A graph consists of a finite set of vertices or nodes and a set of edges connecting these vertices. The order of the graph is the number of vertices in the graph. The size of the chart is the number of sides on the chart. If two nodes are connected to each other by the same edge, the two nodes are said to be adjacent.

• If all edges of graph have a direction, which indicates the initial vertex and the final vertex, then the graph is called a directed graph.
• If all edges of graph have no direction, it is called an undirected graph. It can move in both directions between two vertices.
• If a vertex is not connected to any other node in the graph, it is said to be isolated.