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Electricity has been with us ever since humans first appeared on Earth, in the form of lightening for example, and they created electricity by rubbing materials together. The first machine to generate an electric spark was built about 1650, and worked by rubbing a hand on a spinning sulfur ball. Electrified by friction, the sphere alternately attracted and repulsed light objects from the floor.

In 1733 Charles François de Cisternay DuFay, a French chemist, stated that electricity consisted of two fluids: "vitreous" (from the Latin for "glass"), or positive, electricity; and "resinous," or negative, electricity. When he electrified a glass rod, it attracted nearby bits of cork. But when the rod touched the pieces of cork they were repelled, both from the rod and from repelled one another. DuFay believed that matter contained equal quantities of both types of fluid. If, however, friction separated the fluids in a substance and left it imbalanced, the substance would attract or repel other matter.

The next step was to store the charge created by friction. The Leyden jar was invented about 1750, which could store charge in a glass bottle. Today we use capacitors to store charge in the same way. Many people began to study electricity, and Benjamin Franklin flew a kite in a thunderstorm to prove that lightening was electricity. There was much discussion of whether electricity consisted of two fluids, one positive and the other negative, or just one.

Between 1750 and 1850 the great discoveries in the principles of electricity and magnetism were made by Coulomb, Gauss and Faraday. The battery was invented in 1800 by Volta, so allowing electric current to be used. It was found that electric current could split water into hydrogen and oxygen gases, a process called hydrolysis, that an electric current produces a magnetic field. This led to the invention of the telegraph (1837), the telephone (1876), the electric light bulb (1880) and many other inventions.