INTRODUCTIONTiny organisms which cannot be seen with the naked eye or which require the use of microscopes for their visualization are called microbes. These are studied in the branch of biology known as microbiology. Microbiology mainly concerns the study of viruses, fungi, parasites and bacteria. This also includes the study of the immune system. Microbes are present in all parts of the biosphere, that is, the soil, hot springs, the ocean floor, the atmosphere and the depths of the Earth's crust. They constitute the first form of life on Earth. Their fossils date back more than three and a half billion years, to a time when the Earth was covered in oceans. They have a rapid rate of evolution. They reproduce quickly and are very versatile organisms. The first person to observe microbes was Antonie Van Leeuwenhoek. He established that there were forms of life that were not visible to the naked eye. With Leeuwenhoek, Spallanzani and Pasteur put an end to the long-held belief that life appeared spontaneously from a non-living substance during the process of deterioration. Later, in 1876, Roberto Koch demonstrated that diseases were caused by microorganisms.CHARACTERISTICSMicrobes play a very important role in industry. Here are some important characteristics of microbes that make them industrially important: • They occur quickly. Billions of microbial cells can reproduce in a single day. For example, under optimal growing conditions, E.coli doubles in 15 to 20 minutes. • The medium necessary for their growth is cheap and easily available throughout the year. • They are very versatile and have great biodiversity. They can reproduce and live in extreme conditions of temperature, pH, pressure, salt, etc. • The genotype of microbes of industrial importance if fully known, which is useful for understanding ...... middle of paper ...... 2011). Lactic acid bacteria and bifidobacteria: current progress in advanced research. Caister Academic Press. ISBN 978-1-904455-82-0. Rehm BHA (publisher). (2008). Microbial production of biopolymers and polymer precursors: applications and perspectives. Caister Academic Press. ISBN 978-1-904455-36-3. Lear, G; Lewis, G.D. (editor) (2012). Microbial biofilms: current research and applications. Caister Academic Press. ISBN 978-1-904455-96-7. Okabe, S; Kamagata, et (2010). “Wastewater treatment”. Environmental molecular microbiology. Caister Academic Press. ISBN 978-1-904455-52-3. Ullrich M (editor) (2009). Bacterial polysaccharides: current innovations and future trends. Caister Academic Press. ISBN 978-1-904455-45-5. Diaz E (editor). (2008). Microbial Biodegradation: Genomics and Molecular Biology (1st ed. ed.). Caister Academic Press. ISBN 978-1-904455-17-2.