抄録
Many real systems can be described as networks, composed of a set of nodes and a set of edges connecting the nodes. Interestingly, it has been found that most real networks have a common architecture, termed scale-free or broad-tail topology. Here we review key well-established concepts in network science: small world, scale-free network and network motif, with special emphasis on biological networks. Key mechanisms responsible for the emergence of the scale-free property are discussed along with a simple evolutionary model of protein-protein interaction networks.
