Biofilms are the default mode-of-life for many bacterial species. The variety of microniches provided by the biofilm also promotes a huge diversity of microbial life and metabolic potential. These complex and highly structured communities help to maintain the health of soils and waters. Current applications of biofilms include the degradation of toxic substances in soil and water, the commercial production of chemicals, and the generation of electricity. Biofilm-based infections causes harm to millions of humans annually. In addition, biofilms can affect the quality and yield of crops and cause biofouling and microbial-induced corrosion.