In
graph theory, a
connected component (or just
component) of an
undirected graph is a
subgraph in which any two
vertices are
connected to each other by
paths, and which is connected to no additional vertices in the supergraph. For example, the graph shown in the illustration on the right has three connected components. A vertex with no incident edges is itself a connected component. A graph that is itself connected has exactly one connected component, consisting of the whole graph.