operationsresearch

Operations research, typically abbreviated OR, is a discipline that uses advanced analytical methods to help make better decisions. It builds mathematical models of complex systems and applies scientific methods to optimize performance, often under constraints. OR originated in the 1940s during World War II to improve military operation planning and has since expanded into business, industry, and public sector applications. Key milestones include linear programming and the simplex method developed by George Dantzig, the development of integer and nonlinear programming, network optimization, queuing theory, and the rise of simulation and stochastic methods.

Common methods include optimization (linear programming, integer programming, nonlinear and mixed-integer programming), network models (shortest path, maximum flow, transportation and assignment problems), stochastic and robust optimization, simulation, and heuristic or metaheuristic approaches (genetic algorithms, tabu search). Decision analysis, forecasting, inventory, project scheduling (PERT/CPM), and reliability are also used. The field often combines domain knowledge with data, enabling model-based decision support in uncertain environments.

Applications are broad: supply chain and logistics, manufacturing, transportation, energy, healthcare, finance, military and defense, telecommunications, and service operations. OR is closely related to management science and operations management, emphasizing model-based decision support rather than solely empirical analysis. Tools and software such as linear and integer programming solvers support practitioners, who typically work in cross-disciplinary teams with domain experts. Education programs prepare OR analysts for roles in industry, government, and consulting.