IN THIS CHAPTER
Defining why networks are important
Demonstrating graph drawing techniques
Considering graph functionality
Using numeric formats to represent graphs
Graphs are structures that present a number of nodes (or vertexes) connected by a number of edges or arcs (depending on the representation). When you think about a graph, think about a structure like a map, where each location on the map is a node and the streets are the edges. This presentation differs from a tree where each path ends up in a leaf node. Remember from Chapter 7 that a tree could look like an organizational chart or a family hierarchy. Most important, tree structures actually do look like trees and have a definite start and a definite end. This chapter begins by helping you understand the importance of networks, which are a kind of graph commonly used for all sorts of purposes.