I. Introduction
A network is a collection of interconnected entities, usually consists of nodes and edges. These networks can be simple as well as complex. Networks, sometimes also called as graphs have a great importance in modern network science. Graphs are used in many areas of modern science like biology and chemistry for representing bonds between molecules. Another application of graphs is in sociology, which is the study of structure of human society. A complex network is a large graph of real life. The complex networks [1] include biological networks, Internet and social networks. The study on graph structure for analyzing the relationships between entities yield useful applications [2]. It is difficult to analyze complex networks as we cannot predict how the entities are linked. So to analyze large complex networks, a community structure needs to be formed. Fig. 1 depicts generic work flow of community detection and analysis. Study of complex network using community structure could unfold the entity relationships and patterns.