Math Insight

Edge definition

 

An edge (or link) of a network (or graph) is one of the connections between the nodes (or vertices) of the network. Edges can be directed, meaning they point from one node to the next, as illustrated by the arrows in the first figure below. Edges can also be undirected, in which case they are bidirectional, as illustrated by the lines in the second figure, below.

Small directed network with labeled nodes and edges

A directed network with 10 nodes (or vertices) and 13 edges (or links).

Small undirected network with labeled nodes and edges

An undirected network with 10 nodes (or vertices) and 11 edges (or links).

For more information about network edges, see the network introduction.