_{Sr. Assoc. Vice Chancellor for Research, Distinguished Professor of Mechanical and Aerospace Engineering, University of California, San Diego, Ph.D. University of California, Santa Barbara.}

_{Endowed Chair in Wireless Telecommunications, and McKnight Presidential Chair in ECE Digital Technology Center, Director University of Minnesota, Minneapolis. Ph.D. - University of Southern California.}

_{UPMC professor of Computer Science in the Machine Learning Department, School of Computer Science at Carnegie Mellon University, Ph.D. - University of Toronto.}

_{Scientific director of the Dalle Molle Institute for Artificial Intelligence (IDSIA) Research in Lugano, in Ticino in southern Switzerland, and Professor of Artificial Intelligence (Ordinarius) at the Faculty of Computer Science at the University of Lugano., Ph.D. - Technical University of Munich.}

Control and control theory are fundamental concepts in electrical engineering. Control theory is the branch of engineering that deals with the study of control systems, which are systems that are designed to regulate the behavior of other systems. Control systems can be found in a wide range of applications, including industrial process control, aerospace, and robotics.

Control systems can be divided into two main categories: open-loop control systems and closed-loop control systems. Open-loop control systems rely on pre-programmed instructions to control the system, while closed-loop control systems use feedback from the system to adjust the control inputs. Closed-loop control systems are considered to be more robust and reliable than open-loop control systems because they can adapt to changes in the system.

Control theory is based on mathematical models of systems, which are used to design control algorithms. These models can be in the form of differential equations, state-space equations, or transfer functions. The goal of control theory is to design controllers that can stabilize a system, reduce its sensitivity to disturbances, and achieve desired performance.

One of the key concepts in control theory is feedback. Feedback is the process of using the output of a system to adjust the input, in order to achieve a desired behavior. Feedback control systems are widely used in a variety of applications, such as temperature control, speed control, and position control.

Another important concept in control theory is stability. Stability refers to the ability of a system to return to a desired state after being disturbed. A stable system is one that will not diverge from its desired behavior, even in the presence of disturbances or noise. The study of stability is an important part of control theory and is closely related to the concept of feedback.

Control theory also deals with the concept of optimality. Optimality refers to the ability of a control system to achieve the best possible performance, given a set of constraints. Optimality can be achieved by designing controllers that minimize a certain performance index, such as a cost function.

In conclusion, control and control theory play a critical role in electrical engineering. They provide the theoretical foundation for the design of control systems and are used in a wide range of applications. Control theory is based on mathematical models of systems and uses concepts such as feedback, stability, and optimality to achieve desired behavior of the controlled system. These concepts are widely applied in the industry, for example in aircraft navigation, power systems, and robotic systems.