In electricity, charges produce electromagnetic fields which act on other charges. Electricity occurs due to several types of physics:
- electromagnets: Moving charges produce a magnetic field. Electrical currents generate magnetic fields, and changing magnetic fields generate electrical currents.
In electrical engineering, electricity is used for:
electric power where electric current is used to energise equipment;
- electronics which deals with electrical circuits that involve active electrical components such as integrated circuits, and associated passive interconnection technologies.
Electrical phenomena have been studied on Terra since antiquity, though progress in theoretical understanding remained slow until the seventeenth and eighteenth centuries CE. Even then, it would not be until the late nineteenth century that engineers were able to put it to industrial and residential use. The rapid expansion in electrical technology at this time transformed industry and society. Electricity's extraordinary versatility means it can be put to an almost limitless set of applications which include transport, heating and lighting.