Diagnostic microbiology is the study of microbial identification. Since the discovery of the germ theory of disease, scientists have been finding ways to harvest specific organisms. Using methods such as differential media or genome sequencing, physicians and scientists can observe novel functions in organisms for more effective and accurate diagnosis of organisms. Methods used in diagnostic microbiology are often used to take advantage of a particular difference in organisms attain information about what species it might be, often through a reference of previous studies. New studies provide information that other scientists can reference back to so scientists can have a baseline knowledge of the organism he or she are working with.