Electricity

Electricity is a general term encompassing a variety of physical phenomena resulting from the presence and flow of electric charge phenomena. Most people have observed the effect of static electricity, for example, lightning.

History
The Greek philosopher Thales of Miletus, who lived between c. 624 BC – c. 546 BC, about 2600 years ago, is credited as the discoverer of static electricity. Thales also studied magnetism and recorded that when he rubbed amber it could attract small pieces of straw or thread. Magnetism had been discovered about 100 years before Thales and it was named by the Greeks for the province of Magnesia in Asia Minor, where the stones were first found. William Gilbert (1544–1603) made some progress in the sixteenth century comparing the effects of electricity and magnetism. Benjamin Franklin (1706–1790) attempted to prove that lightning in the sky was the same as electricity by performing his famous experiment. The new science of electromagnetism was developed further in the nineteenth century by scientists like Michael Faraday and James Clerk Maxwell who put Faraday’s ideas into mathematical form.

Properties
The ancient Greeks observed two important properties of electricity:
 * Charged objects can either attract or repel each other.
 * The repulsion occurs when two objects of similar charges are placed near each other, and the attraction occurs when two oppositely charged objects are placed near each other.