A smart system uses a feedback loop of data, which provides evidence for informed decision-making. The system can monitor, measure, analyse, communicate and act, based on information captured from sensors. Different levels of smart systems exist. A system may:

• collect usage and performance data to help future designers to produce the next, more efficient version;

• collect data, process them and present information to help a human operator to take decisions (for example, traffic systems that detect congestion and inform drivers);

• use collected data to take action without human intervention