An intelligent system is a machine with an embedded, Internet-connected computer that has the capacity to gather and analyze data and communicate with other systems. Other criteria for intelligent systems include the capacity to learn from experience, security, connectivity, the ability to adapt according to current data and the capacity for remote monitoring and management.
In IT, a system is defined as a collection of connected elements or components that are organized for a common purpose. As such, although they are typically spoken of in terms of devices, intelligent systems include not just intelligent devices but also interconnected collections of such devices, including networks and other types of larger systems. Similarly, intelligent systems can also include sophisticated AI-based software systems, such as chatbots, expert systems and other types of software.
Essentially, an intelligent device is anything that contains a functional, although not usually general-purpose, computer with Internet connectivity. An embedded system may be powerful and capable of complex processing and data analysis, but it is usually specialized for tasks relevant to the host machine.
Intelligent systems exist all around us in point-of-sale (POS) terminals, digital televisions, traffic lights, Smart meters, automobiles, digital signage and airplane controls, among a great number of other possibilities. Built-in intelligence is an integral component of the developing internet of things (IoT), in which almost everything imaginable can be provided with unique identifiers and the ability to automatically transfer data over a network without requiring human-to-human or human-to-computer interaction.
See Alex Wissner-Gross' TED talk, A new equation for intelligence: