Decision theory is a field of study that focuses on the principles and methods for making choices under uncertainty. It combines elements from mathematics, statistics, and psychology to analyze how individuals and organizations make decisions. The goal is to identify the best possible option based on available information and potential outcomes. There are two main branches of decision theory: normative and descriptive. Normative decision theory provides guidelines for how decisions should be made to achieve the best results, while descriptive decision theory examines how people actually make decisions in real-life situations. Understanding both aspects helps improve decision-making processes.