This book examines the usage of probiotics and its positive effects. Over the last few decades, the prevalence of research regarding probiotics strains has significantly grown in most regions of the world. Probiotics are particular strains of microorganisms, which when served to animals or humans in suitable amount, have an advantageous impact, enhancing health or decreasing the risk of getting sick and the probiotics are employed in production of functional foods and pharmaceutical products. The book contains the complete information regarding issues such as probiotics in health, in biotechnological aspects and its use in aquaculture which will serve extremely helpful for the people related to this field across the world.