In medicine, biotechnology and pharmacology, drug discovery is the process by which drugs are discovered and/or designed.In the past most drugs have been discovered either by identifying the active ingredient from traditional remedies or by serendipitous discovery.A new approach has been to understand how disease and infection are controlled at the molecular and physiological level and to target specific entities based on this knowledge.The process of drug discovery involves the identification of candidates, synthesis, characterization, screening, and assays for therapeutic efficacy.Once a compound has shown its value in these tests, it will begin the process of drug development prior to clinical trials.