Water is a medium where organisms thrive and attach to virtually all materials leading to biofilm formation and fouling. Biofilms on iron, the most widely employed metal on earth, cause severe material loss - corrosion values as high as 1 mm per year - by biocorrosion, such as accelerated low water corrosion, and microbial induced corrosion by sulfate reducing bacteria. Biocorrosion encompasses even interesting ecological and evolutionary aspects, becoming a topic in the field of 'electro-microbiology'.
In order to develop strategies that minimize the costs of corrosion in shipping, offshore, harbor, petrochemical structures, pipelines, etc., it is essential to have a deep understanding of these phenomena from a scientific point of view. Biocorrosion is an essay, reviewing the relevant scientific papers, brought together, in order to be as convincing as possible. The authors are excessively cited, and the references are listed at the end of the document, as a source for personal documentation.