The study of microscopic organisms is called microbiology. Micro-organisms are very small organisms which are not visible through naked eye. These organisms include algae, bacteria, moulds, protozoa, yeasts and viruses. Sometimes they are even referred to as microbes and are studied under microscope, being very small in appearance.

Micro-organisms are almost found everywhere and they constitute by far the largest group of living things existing on earth. Our existence, health, food, agriculture and even industrial development are very much dependent on them. If microbes were to become extinct, disaster would become inevitable and would be beyond imagination. Unknowingly, man has made use of micro-organism since prehistoric times, mostly in the production of food and drinks, such as leavening of bread, souring of milk and making of wine and beer etc. However, it was only in the seventeenth century that the microbial world was discovered.

Microbiologists study and investigate micro-organisms and their relationships with man, animals and plants. Some of the sub-categories of microbiologists are as follows.

1. MEDICAL MICROBIOLOGISTS: Medical microbiologists study the role played by micro-organisms in inflicting diseases in humans and animals. They research and investigate these organisms to find ways to cure and prevent, occurrence of these diseases. Major breakthroughs have been made in this field and efforts are on all over the world to find solutions to many more dreadful diseases especially AIDS.

2. AGRICULTURAL MICROBIOLOGISTS: India is still an agricultural economy and microbiologists play an important role in improving it's size and shape i.e.the output and quality. Agricultural microbiologists study plant diseases, the role of micro-organisms in soil fertility and spoilage of farm products. Advances and inventions made in agricultural microbiology over the years has contributed in increasing agricultural output.

3. INDUSTRIAL MICROBIOLOGISTS: Industrial microbiologists work with industries producing products such as alcoholic beverages, amino acids, citric acids, Vitamin C and antibiotics etc. with the help of micro-organisms.

4. MARINE MICROBIOLOGISTS: Marine microbiology deals with the micro-organisms present in the ocean. It is a relatively new division of microbiology and promises to be an exciting one.

5. GENERAL MICROBIOLOGISTS: General microbiology focuses on the fundamentals and basic features of micro-organisms including ecology, metabolism, genetics, physiology and structure.

Microbiology like any other research related science field requires utmost dedication apart from having scientific and analytical temper, interest in research, observant attitude, deligence, ability to work in team of professionals, good communication skills and hardwork. Good mathematical and computational skills are of added advantage.

Microbiology being a science subject can be pursued by candidates with background in science at the school level. B.Sc. and further M.Sc. courses can be taken up at the institutions and universities offering these courses.

Biologists can further specialize in the study of micro-organisms in the fields of their interest such as bacteriology ; study of bacteria, mycology ; study of fungi and virology ; study of viruses.

Microbiologists find jobs in many places like research and development laboratories of government and private hospitals, research organisations, pharmaceutical, food, beverage and chemical industries. Being closely related to biotechnology, there are many similarities between them, making microbiology also a very promising career option. A steep rise in employment avenues for microbiologists is envisaged as a result of growing numbers of above mentioned organisations.