Graph Theory Basics Part - 1

A graph contains two components

1. Vertex or sometimes called as nodes
2. Edges - An Edge connects Two nodes.

Example ::

 

Types of graphs :

Mainly there are two types of graphs

1. Directed graph
2. Undirected graph

 Directed graph - A graph in which whose direction of edges are defined is called directed

 graph.

 Undirected graph -  A graph in which whose direction of edges are not defined is called 

undirected graph.

Examples :

  Next we will see another sets of graph called connected graph and complete graph.

Connected graph - A graph is said to be connected if there exist a path between every

 pair of vertices.  Note that every vertex will have at least a single edge connected 

 to it. 

We must understand that a connected graph will have its vertices connected that

 doesn't mean that a single vertex must connect with every other vertices in the graph.

Complete graph - A complete graph is also a connected graph but with this special 

condition.

The condition is that every vertex in the graph must connect with all the other

 vertices in the graph.

Here on the above diagram we can see that every node/vertex  is connected to

 every other nodes in the graph. Here all nodes are adjacent to each other. 

Next read on the topic “ Types of graphs on the basis of Edges “.