IoT devices are physical objects that are designed to interact with the real world in some way and are programmed for certain applications. They are embedded with sensors, processing ability, software, and other technologies that connect and exchange data with other devices and systems over the Internet or other communications networks. IoT devices can be categorized into three main groups: consumer, enterprise, and industrial. They can range from small ordinary household cooking appliances to sophisticated industrial tools. Some examples of IoT devices include sensors on an assembly line, intelligent appliances, environmental sensors, medical devices, and more. IoT devices can be controlled via devices associated with that ecosystem, such as smartphones and smart speakers. IoT devices are a part of the larger concept of home automation, which can include lighting, heating and air conditioning, media and security systems, and camera systems.

IoT devices have both industrial and consumer uses and are typically integrated into other tools such as mobile devices, industrial equipment, and medical devices. They are used to send data or interact with other IoT devices over a network, and they aid in making daily activities faster, easier, or more convenient for consumers while also providing real-time data for industrial or enterprise use cases. Increasingly, IoT devices are using AI and machine learning to bring intelligence and autonomy to systems and processes, such as autonomous driving, industrial smart manufacturing, medical equipment, and home automation.

Different IoT devices have different functions, but they all have similarities in that they have at least one transducer (sensor or actuator) for interacting directly with the physical world and at least one network interface (e.g., Ethernet, Wi-Fi, Bluetooth) for interfacing with the digital world.