Branches of microbiology
The branches of microbiology can be classified into pure and applied sciences. Microbiology can be also classified based on taxonomy, in the cases of bacteriology, mycology, protozoology, and phycology. There is considerable overlap between the specific branches of microbiology with each other and with other disciplines, and certain aspects of these branches can extend beyond the traditional scope of microbiology
In general the field of microbiology can be divided in the more fundamental branch (pure microbiology) and the applied microbiology (biotechnology). In the more fundamental field the organisms are studied as the subject itself on a deeper (theoretical) level.
Applied microbiology refers to the fields where the micro-organisms are applied in certain processes such as brewing or fermentation. The organisms itself are often not studied as such, but applied to sustain certain processes.
Geomicrobiology
A common field of study within geomicrobiology is origin of life on earth or other planets. Various rock-water interactions, such as serpentinization and water radiolysis, are possible sources of metabolic energy to support chemolithoautotrophic microbial communities on Early Earth and on other planetary bodies such as Mars, Europa and Enceladus.