How electricity changed the world

"Electricity is the lifeblood of contemporary society. But the bright, modern-day world lit up by coal, natural gas, nuclear power, and renewable energy sources is a relatively new phenomenon. From the time prehistoric people lived in caves until little more than a century ago, the world was dark at night. People lit wood fires and burned candles made from animal or vegetable fat. The incandescent light bulb invented by Thomas Edison did more than allow people to see better in the dark. Artificial lighting also altered the biological rhythms of life that had guided humanity for thousands of years. But further developments in renewable electricity will continue to fuel progress and change lives well into the next century"--Provided by publisher.