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.
Geobiology
Astrobiology is an interdisciplinary field that uses a combination of geobiological and planetary science data to establish a context for the search for life on other planets. The origin of life from non-living chemistry and geology, or abiogenesis, is a major topic in astrobiology. Even though it is fundamentally an earth-bound concern, and therefore of great geobiological interest, getting at the origin of life necessitates considering what life requires, what, if anything, is special about Earth, what might have changed to allow life to blossom, what constitutes evidence for life, and even what constitutes life itself. These are the same questions that scientists might ask when searching for alien life. In addition, astrobiologists research the possibility of life based on other metabolisms and elements, the survivability of Earth’s organisms on other planets or spacecrafts, planetary and solar system evolution, and space geochemistry.