Electricity is the most widely used form of energy, ranging from miniature batteries in your wristwatch to large arc furnaces for melting steel. It's important to understand electricity's basic principles to see how to use it wisely and safely.
Our first understanding of electricity began about 600 B.C. with the observed attraction between materials and amber rods rubbed with other materials. This is how the name electricity was derived.
Ironically, electricity must be converted to other forms of energy such as heat, light, or mechanical power to be useful. In fact, Thomas Edison himself never thought electric power could be sold, since power itself had no "value". He thought people would have to be sold light or heat - a thought that is coming back into vogue today as "end-use pricing".