Check out this encyclopedia entry for some biofilm basics
Lappin-Scott, H., & Costerton, J. W. (2007). Biofilm. In McGraw-Hill Encyclopedia of Science & Technology (10th ed., Vol. 3, pp. 30-32). New York, NY: McGraw-Hill. Retrieved from https://link.gale.com/apps/doc/CX3057500739/GVRL?u=taco25438&sid=GVRL&xid=d05638c7