We will finish this chapter with the basics of graph and network visualization in Mathematica. This is an active area of research, and there are robust and powerful software that can render very big graphs using smart data structures and graph-rendering algorithms. Mathematica is not the best tool out there for a visualization scientist who would like to render very big graphs. However, for small- to medium-sized graphs (for example, a few thousand nodes), Mathematica provides very nice visualization functions and a lot of network analysis packages.

A graph consists of nodes (often called vertices, plural of vertex) and edges, where nodes store information for any particular data type, and edges are the relationships between the nodes. An edge connects two nodes. Edges can be directed (connect nodes one way) or undirected. Social networks are often described with graphs to denote relationship between friends and family. More interestingly, many real-world problems can...