What are the different types of microorganisms?

The five types of microorganisms that are not visible to the naked eye are bacteria, viruses, algae, fungi, and protozoa, and exist in a wide range of environments, from soil and water to living organisms like plants and animals. Bacteria are single-celled organisms that play important roles in the environment, including the nitrogen cycle and decomposition. Viruses are not considered living organisms, but they can cause diseases in humans and other animals. Algae are photosynthetic microorganisms that can be found in marine and freshwater environments. Fungi include yeasts and molds and can be found in soil, water, and living organisms. Protozoa are single-celled eukaryotes that can be found in soil, water, and the digestive tracts of animals. Understanding the characteristics and functions of these different types of microorganisms is important for fields such as microbiology, ecology, and biotechnology.