Veillonella is a genus of bacteria that are commonly found in the human mouth and gut. These bacteria are anaerobic, meaning they thrive in environments without oxygen. They play a role in breaking down lactic acid, which can be beneficial for maintaining a balanced microbial community in the body. In addition to their presence in humans, Veillonella species are also found in various animals and environmental samples. Some studies suggest that these bacteria may have a role in oral health and could be linked to certain health conditions, making them an interesting subject for further research in microbiology.