The case method, or case study, is a method of research used in a variety of disciplines that identifies a single example, a few selected examples, or a particular phenomenon.
Case studies may sometimes be a part of comparative research (identifying similarities and differences between two examples), and sometimes is meant to be close, detailed examination.
Case studies typically rely more on qualitative studies than quantitative studies, and some fields use examination of 'classic' cases as a method of training.
Case studies are used in business, medicine and health, journalism, psychology, anthropology, law, epidemiology, human geography, and other social sciences.