what are bacteria
Bacteria are microorganisms too small to see with the naked eye that exist in virtually all environments in the world. They exist in dirt, water, caves and hot springs, organic materials like fallen trees and dead animals, and inside the bodies of virtually every living animal on earth.ut fortunately, not all bacteria are harmful. A number of the bacteria found in the human body have positive benefits for their host. They can help strengthen the immune system, help digest food, secrete hormones and chemicals and vitamins that benefit the health of the human body, and help regulate human metabolism.