The Earth is absolutely covered in bacteria
Bacteria are microorganisms that are mostly known for causing diseases. Nevertheless, they do a lot of good as well. Some live inside us and help us in vital processes such as digestion, while others found in the soil, sediments, and seas help plants grow.
Another process in which bacteria play an essential role is in matter decomposition. This keeps soils nutrient-rich and nature cycles healthy. It is estimated that about 4 quadrillion quadrillions of these microorganisms are on the planet.