The networks have evolved significantly as a central tool in the study of complex systems. The language of nodes and edges provided by networks has proven to be very illustrative of model elements of a system (nodes) and their interactions (edges). The properties of complex networks include the small-world effect, scale-free topologies, modularity, robustness, evolvability, degeneracy, and redundancy. Brede reports a model of network generation, where the rates of random addition of nodes and optimal rewiring are explored to generate complex networks with power law tails in degree distributions, hierarchies, nontrivial clustering, and degree-mixing patterns. Droop and Hickinbotham use an artificial chemistry to study the properties of networks constructed from mutation patterns observed in nature. The resulting small-world networks offer a balance between random and regular topologies. Brede studies illustrate the nontrivial relationship between network topology and the facilitation of the evolution of cooperation.