From Wolfram Alpha :
A simple graph, also called a strict graph, is an unweighted, undirected graph containing no graph loops or
multiple edges. Unless stated otherwise, the unqualified term "graph" usually refers to a simple graph. A simple graph with multiple edges is sometimes called a multigraph.
What does multiple edges mean here ? And does graph loop mean self loops ?
Most reasonable graphs will contain more than one edges. So I am a little bit confused with the term multiple edges.