What are the major groups of microorganisms?

Explanation

There are five major groups of microorganisms.
(i) Bacteria which are non-green, single-celled microorganisms.
(ii) Fungi which are long thread-like unicellular as well as multicellular microorganisms.
(iii) Algae which are aquatic, photosynthetic organisms.
(iv) Protozoa which are unicellular organisms.
(v) Viruses which are non-cellular microbes, that only get active inside a living cell.