To date, modern researchers in various fields have come with new definitions on networks, but they have relied on research work that has existed for the last two centuries. Albert-Laszlo Barabasi is one such modern researcher who has redefined the concept of networks based on research work done for the past 250 years. According to Barabasi, networks are made up of few nodes connected to multiple sites, terming them scale-free networks. This new development has changed the way people knew about the complexity of many networks that exist today. Theories that have previously been in existence did not explain that various and complex systems contain strict designs ruled by fundamental laws (Barabási 2003, p.77).
Before the discovery of scale-free networks, scientists believed that all complex networks are entirely random. This could be easily demonstrated by connecting nodes to randomly placed links. This description of networks indicates that every node in the network will be connected to the same number of links (Caldarelli 2007, p. 44). This network connection follows a Poisson distribution, which is characterized by a bell-shaped graph. Random network connections have been the basis for networking for a long time. this happened until Barabasi and colleagues came up with the software that could prove whether random network connections exist. The use of the software in this study enabled the researchers to discover that a few but highly connected pages hold the World Wide Web together (Barabási 2003, p.65).
This research further revealed that scale-free networks follow the so-called power-law distribution rather than the bell-shaped distribution that is characteristic of random networks. Therefore, in the scale-free networks, the majority of nodes have a limited number of connections, and others have a high number of links. This is what makes the network to be free of “scale”. The key characteristic of the scale-free network is that distribution of links when plotted on a double-logarithmic scale will yield to a straight line (Sergeĭ & Dorogovt︠s︡ev 2003, p.47). The study points out that many of the networks that occur naturally tend to be self-organized into a form of hub-based network.