This tutorial illustrates how a galvanometer, an instrument that detects and measures small amounts of current in an electrical circuit, works. (Java tutorial)

Keith Richards and Eric Clapton owe their fame and fortune (in part) to electromagnetic induction. (Java tutorial)

In 1906, American physicist Lee De Forest invented the Audion (or triode), building on John Fleming's discovery of the diode just a few years before.

Invented decades before it could be used, the first type of electric light was so brilliant it was used for lighthouses and street lamps.

Alternating current behaves differently, depending on what components are in a circuit.

English chemist John Frederick Daniell came up with a twist on the simple voltaic cell that resulted in a longer-lasting source of power.

This tutorial illustrates how the flow of water through a system of pipes can be used to understand the flow of current through an electric circuit.

Many people interact with cathode ray tubes for part, if not most, of the day without having a clue how they work. Here's the inside scoop. (Java tutorial)

A capacitor is similar to a battery in that both store electrical energy. But a capacitor can't actually produce new electrons; it only stores them.

This tutorial takes a shot at explaining how circuits can be used to measure things beyond the capacity of human senses.

English mathematician Peter Barlow devised an instrument in 1822 that built on advances from earlier in the century (including the invention the battery) to create a very early kind of electric motor.

Electric motors turn electricity into motion by exploiting electromagnetic induction.

Out of a humble ice pail the great experimentalist Michael Faraday created a device to demonstrate key principles of attraction, repulsion and electrostatic induction. (Java tutorial)

Just a year after electromagnetism was discovered, the great scientific thinker Michael Faraday figured out how to turn it into motion. (Java tutorial)

Though simple by today's standards, the early electrostatic generators were a great milestone in humankind's understanding of electricity, allowing scientists to produce electricity so they could study it. (Java tutorial)

When electricity became available to the masses, utilities needed meters to record customer usage. This early 20th century model resembles many in use today. (Java tutorial)

Mass spectrometers are machines that give scientists a look at the composition and origin of a material by analyzing and quantifying its atoms and molecules. This tutorial shows how a dual sector mass spectrometer works. (Java tutorial)

These devices, though quite humble, represented a tremendous breakthrough in the history of electricity; they were the first capacitors, and as such were able to store electric charge. (Java tutorial)

The legendary Lord Kelvin made electricity from water with this ingenious electrostatic generator. (Java tutorial)

This Java tutorial is a three-dimensional simulation of a cathode ray oscilloscope producing Lissajous figures as it compares sinusoidal voltages.

Invented by William Thomson (who later became Lord Kelvin for such clever acts as this), the mirror galvanometer was a useful instrument that played a key role in the history of the telegraph. (Java tutorial)

What makes those kernels pop inside your microwave? A whole lot of water interacting with a whole lot of high-frequency electromagnetic waves. (Java tutorial)

Sir Oliver Lodge's experiment demonstrating the first tunable radio receiver was an important stepping stone on the path toward the invention of a practical radio.

Two heads - or even three - are better than one when it comes to understanding how tape recorders exploit electromagnetic induction. This is a Java tutorial that explains how tape recorders reproduce sound.