This document provides an overview of operational research. It begins with definitions, describing it as the scientific study of operations to make better decisions. It discusses the history, noting it originated from military planning in World War II and has since expanded to other fields. The objectives are outlined as improving decision making and identifying optimal solutions. The scope includes various sectors like health, defense, business and agriculture. Methods typically involve simulation, optimization and data analysis. The operational research process is also summarized as identifying problems, potential solutions, testing solutions, disseminating results. Applications in public health are discussed along with composition of operational research teams and the process. Finally, it briefly outlines some key societies and journals in the field like IFORS and INFORMS