The technology that allows users to control devices through smart assistants includes voice recognition and natural language processing systems. Smart assistants, such as Amazon's Alexa or Google Assistant, utilize these technologies to understand and respond to user commands. Users can interact with their smart devices through voice commands to perform tasks like turning on lights, adjusting thermostats, or playing music. This user-friendly interface enhances accessibility and convenience while promoting the adoption of Internet of Things (IoT) devices in everyday life.