Electricity

Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire. In addition, electricity encompasses less familiar concepts such as the electromagnetic field and electromagnetic induction.

The word is from the New Latin ēlectricus, "amber-like", coined in the year 1600 from the Greek ήλεκτρον (electron) meaning amber (hardened plant resin), because electrical effects were produced classically by rubbing amber.

In general usage, the word "electricity" adequately refers to a number of physical effects. In a scientific context, however, the term is vague, and these related, but distinct, concepts are better identified by more precise terms:

• Electric charge: a property of some subatomic particles, which determines their electromagnetic interactions. Electrically charged matter is influenced by, and produces, electromagnetic fields.
• Electric current: a movement or flow of electrically charged particles, typically measured in amperes.
• Electric field: an influence produced by an electric charge on other charges in its vicinity.
• Electric potential: the capacity of an electric field to do work on an electric charge, typically measured in volts.
• Electromagnetism: a fundamental interaction between the magnetic field and the presence and motion of an electric charge.

The most common use of the word "electricity" is less precise. It refers to:

• Electric power provided commercially by the electrical power industry. In a loose but common use of the term, "electricity" may be used to mean "wired for electricity" which means a working connection to an electric power station. Such a connection grants the user of "electricity" access to the electric field present in electrical wiring, and thus to electric power.

Electrical phenomena have been studied since antiquity, though advances in the science were not made until the seventeenth and eighteenth centuries. Practical applications for electricity however remained few, and 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 as a source of energy means it can be put to an almost limitless set of applications which include transport, heating, lighting, communications, and computation. Electrical power is the backbone of modern industrial society, and is expected to remain so for the foreseeable future.