Optimal control is a branch of control theory that focuses on finding the best control inputs to a system in order to optimize its performance or achieve a specific objective. This field is concerned with determining the optimal control strategy that minimizes a cost function while satisfying system constraints. Optimal control is used in a wide range of applications, including robotics, aerospace, economics, and engineering, to improve the efficiency and effectiveness of systems. Researchers in this area develop mathematical models, algorithms, and techniques to solve optimization problems and design optimal control strategies for complex systems.