Simple graph- every edge is connected to two different vertices; no two edges can be connected to the same pair of vertices.
Pseudograph- may consists of multiple edges (loops) and are also non simple.
There are many types of graphs
when looking into graph theory. Some of the two basics are directed and
undirected. A directed graph is a graph that contains edges connected by one
vertex to the next. An undirected graph however, has vertices that are
connected by edges that are bidirection.
Graph theory also consists of
graphs that apply different rules such as the Eulerian graph and the
Hamiltonian graph. The Eulerian graph is a graph that has an even degree for
each of its vertices and has to be connected.