Classification of Microbes

Virus

• A virus is any small microbe capable of reproducing and growing in any living cell (that is, in the cell of any living creature). This type of microbe is considered to be infectious in nature, and their reproduction process inside any other life form leads to the creation of diseases and infections. Viruses are the most abundant category of microbes present around (which exist primarily for their reproduction), and are the only life forms on Earth which have millions of sub-categories and types associated with them.

Bacteria

• Bacteria is another abundant category of microbes, which (unlike viruses) are present on every single inch of Earth's surface, and do not require a living cell to grow inside. These microbes are mostly non-infectious in nature, and are considered to be the supportive elements of life on Earth. There are many sub-categories and types of bacteria, and most of them are classified according to their unusual shapes (i.e. stick-shaped, helical, spherical, etc.). Although bacteria do not need any particular environment for their reproduction, they primarily feed on plants, animal skins, moisture, liquids, and transmit from one place to another through different carriers like humans, animals, reptiles, birds, and insects.

Algae

• This type of microbe is strictly found on plants, rocks, and soil, and requires sufficient amount of moisture to grow. Algae are relatively larger (as compared to bacteria and viruses) microbes that feed on sunlight with moisture, and are prime contributors in the creation of oxygen that humans and other living things breathe. Although most algae are unicellular organisms, some classes are multicellular, which have properties identical to that of plants.

Fungi

• Fungi (plural for fungus) are a unique type of microbes, which should not be mistaken as plants, animals, or even bacteria. These microbes are small living creatures, which have properties partially identical to plants and animals, and for this reason, are classified under a totally different category of microbes. Fungi are also abundant in nature, and their classes range from microscopic to giant. There are multiple types of fungi, and out of them, the most commonly observed ones are mushrooms growing in moist places, small organisms appearing over piece of bread, or over animal skins.

Protozoa

• Protozoa are another major category of microbes, which primarily survive by feeding on bacteria and fungi. These microbes are considered to be tiny animals by microbiologists. Since they hunt other microbes for their survival, do not (primarily) need a carrier to move from one place to another, and have a stomach-like mechanism which digests their food. Protozoa are usually harmful for living beings, and if transmitted inside animal bodies (through water or food), can cause several diseases which can lead to severe allergies and infections.