In mechatronics, sensors, actuators, and controllers form the core building blocks of any automated system. Sensors detect changes in the environment or system conditions and provide crucial data as input signals. Controllers interpret this data, apply decision-making or control algorithms, and send commands to actuators. Actuators then convert these commands into physical action, such as movement, force, or switching. Working together, these three elements create closed-loop systems that enable precision, adaptability, and efficiency in applications ranging from robotics and industrial automation to consumer electronics.