Lactobacillus is a genus of bacteria that are commonly found in human and animal intestines, as well as in various fermented foods. These bacteria are often referred to as probiotics because they provide health benefits when consumed in adequate amounts. They play an important role in maintaining the balance of microorganisms in our gut and help with digestion, immune system support, and overall well-being. Some species of lactobacillus are also used in the production of yogurt, sauerkraut, kimchi, and other fermented foods.