## Isolated Vertices

In the beginning, in the family name
*
Graph
*
, there is a point. This point is called a
*
vertex
*
. It is an isolated point of Graph. It feels so lonely.

Then there is another point, which also identifies itself as a vertex. These two points requested to be called
*
vertices.
*

Now the two vertices are isolated points of a Graph. They are not connected. A graph no needs to be connected.

Teknomo, Kardi (2015) Pictorial Introduction to Graph Theory. http:\\people.revoledu.com\kardi\tutorial\GraphTheory\