Abstract
Microbial communities are the assemblies of microorganisms which live collectively on a surface being encapsulated in a matrix of extracellular polymeric substances (EPS). This particular form of the lifestyle which is collective in nature and shares the common living space is known as biofilm—the most familiar form of bacterial growth. In the last few decades, a considerable number of researches have been dedicated towards the search for mechanisms behind the biofilm growth. In this chapter, we provide a description of the collective and social microbial behavior of biofilm with underlying mechanism for better understanding of the fundamental mechanisms behind the biofilm formation. Our aim is to describe the collective behavior of the microbial community with specific emphasis on the physical process of the biofilm development on the basis of statistical theory and hydrodynamics. The physical process of biofilm formation often encounters the phenomena of pattern formation and is influenced by the external parameters such as environmental stress conditions and nutrient limitation. Finally, we accumulate some recent significant observations on biofilms.