1. A graph consists of a set of vertices and a set of edges that connect two vertices
2. Self-loop: There is a variable connecting the fixed point and itself in the graph.
3. Parallel edges: Two edges connecting the same pair of vertices are parallel edges.
4. A graph with parallel edges is called a multigraph, and a graph without parallel edges or self-loops is called a simple graph.
5. Vertex Degree: The number of edges attached to a vertex. Subgraph: A graph consisting of a subset of all edges of a graph and all vertices to which they are attached.
6. Path Simple Path Ring Simple Ring Acyclic Graph
7. Connected graph: If any vertex in the graph has a path to another vertex.
Determine whether it is a bipartite graph