Probiotics are a combination of live beneficial micro-organism i.e. bacteria and yeast that are intended to have health benefits when consumed or applied to the body. Probiotics have become more popular in the past two decades, the most common fermented foods that naturally contain probiotics, or have probiotic added to them, include Yogurt, Kefir, Kombucha, Sauerkraut, Pickles, Miso, Temph, Kimchi, Sourdough bread, and some cheeses. Probiotic bacteria are Lactobacillus, Bifidobacterium, Streptococcus Thermophilus, Bulgaricus, Propionobacterim etc., after dissecting and examining the various significant strains that may be incorporated in probiotic supplements, it becomes obvious why they are valuable for maintaining your overall health. They give a lot of added health advantages. Prebiotics are beneficial components of probiotic supplements that support and promote health in almost all body systems. With the application of various products, more scientific evidence shows that probiotics are beneficial to human health, and the food industry is very active in researching and promoting them. Given this continuing trend, although there is strong scientific evidence linking these microbes to different health benefits, more research is required to identify them and evaluate their safety and nutritional aspects. The goal of this book is to assess the current literature on the concept and potential beneficial elements of probiotics in the literature, with a focus on probiotics in food and medicine.