What is a scale free network ?

So, what does "scale-free" mean anyway ? This article - Scale Free Networks offers up a good explanation. In a nutshell, a scale-free network is a network where links between nodes aren't added or distributed randomly. Iinstead of random attachment, you get preferential attachment - ie the more links a node already has, the greater the probability of a new node attaching to it. Applied to the internet, you see this in super-connected sites such as Yahoo, Google, etc. In a social networking model, these hubs are generally known as "connectors", and are normally responsible for bringing together disparate groups.