Which type of bacteria is considered non harmful?

Non pathogenic bacteria are types of bacteria that do not cause disease or harm to the host. They can exist peacefully in environments, including on human skin and within the human body, often playing beneficial roles such as aiding in digestion or protecting against harmful bacteria. This characteristic is central to their classification as non pathogenic.

In contrast, pathogenic bacteria are harmful and can lead to infections and diseases. Facultative bacteria refer to those that can grow in both the presence and absence of oxygen, which does not inherently relate to their harmfulness. Aerobic bacteria specifically require oxygen for growth, but whether they are harmful or not varies among different bacterial species. Understanding the basic classification of bacteria helps in recognizing the roles they play in health and disease, clarifying why non pathogenic bacteria are considered a benign group.