Two remarkable features Scale-free topology k Modular organization k For a large number of real networks these two features coexist. k Protein interaction network k Metabolic networks k The World wide Web k Some social networks Scale-free topology  Modular organization  For a large number of real networks, these two features coexist:  Protein interaction network  Metabolic networks  The World Wide Web  Some social networks  … … Two remarkable features 20:19:48