Long before the iPhone, the iPod or even the Mac, there was the Apple.

The first compass was used not to point people in the right direction literally, but figuratively.

Although it never quite measured up to expectations, the Edison battery paved the way for the modern alkaline battery.

Compared to incandescent lamps, fluorescent lamps last longer, require less energy and produce less heat, advantages resulting from the different way in which they generate light.

Otto von Guericke's electrostatic machine evolved into increasingly improved instruments in the hands of later scientists. In the early 1700s, an Englishman named Francis Hauksbee designed his own electrostatic generator, a feat stemming...

For centuries, the electroscope was one of the most popular instruments used by scientists to study electricity. Abraham Bennet first described this version in 1787.

A very primitive capacitor, this early device allowed scientists to give discs of metal a specific charge.

If TV medical dramas have taught us anything, it's how to recognize the heart's characteristic peaks and valleys crawling across monitors in emergency rooms. These images represent the electrical activity of the beating heart as recorded...

Counting alpha particles was tedious and time-consuming work, until Hans Geiger came up with a device that did the job automatically.

Because they could store significant amounts of charge, Leyden jars allowed scientists to experiment with electricity in a way never before possible.

With only minor changes to its original 1866 design, the Leclanche cell evolved into modern alkaline batteries and the most popular household battery to date.

Found in more homes than any other appliance, the kettle has steadily evolved from an ancient tool to an important modern convenience.

American inventor Vladimir Zworykin, the "father of television," conceived two components key to that invention: the iconoscope and the kinescope.

The first hydroelectric power plant, known as the Vulcan Street Plant, was powered by the Fox River in Appleton, Wisconsin.

The magneto helped fire up the first generation of automobiles.

French physicist Gaston Plante invented the first rechargeable battery, leaving an enduring legacy in battery history. To see it, just pop the hood of your car.

Many heads, hands and hearts contributed to the development of this lifesaving device.

From the auto shop to the doctor's office, the oscilloscope is an important diagnostic tool. A mechanic may use an oscilloscope to measure engine function, while a medical researcher uses it to monitor heart activity.

The man most commonly associated with the telegraph, Samuel Morse, did not invent the communications tool. But he developed it, commercialized it and invented the famous code for it that bears his name.

A number of distinguished scientists had a hand in the discovery of "wireless telegraphy," but it was the work done by Guglielmo Marconi that is credited with providing the basis of radio as we know it today.

Although they have applications at the highest levels of scientific research, magnetron tubes are used every day by non-scientists who just want to heat their food in a hurry.

For thousands of years, electricity was an ephemeral phenomenon- there one second and gone the next. The voltaic pile changed that forever.

What's behind the cool purple sparks? Neat science about resonance and transformers. Slideshow: [6:00]

By the late 1800s, electricity had long been discovered and was no longer considered a novelty. The science of how to store, enhance, or transmit electrical current was just beginning to evolve, and eccentric scientist Nikola Tesla...