Fermentation technologists consider microorganisms as chemical factories in miniature. Microorganisms have the capacity to convert raw material into end products. If the end products have the value for human use, then it becomes attractive to exploit the microbial process to produce the end products on a commercial scale. Fermentation is the biochemical activity of microorganisms on its growth, physiological development, reproduction and even its death. Microbial cells synthesize a tremendous variety of chemical compounds that range from the relatively simple sugars, amino acids, fatty acids, complex antibiotics and pigments to the most complex proteins and polysaccharides. Chemically they can be classified under various categories like organic acids, amino acids, solvents, lipids, alkaloids, peptides, proteins, carbohydrates etc. Functionally these compounds can be classified under various categories like antibiotics, enzymes, flavours, flavour enhancers, hormones, pesticides, pigments, vitamins, enzyme inhibitors etc. Fermentation is the most mature area of Biotechnology. Whatever potential Biotechnology has for expansion amongst the vast array of living forms by genetic manipulation, we will invariably end up with some form of fermentation and the requirement for a fermentor where microorganisms are cultivated.