Did You Know?
Since the early 19th century, "fossil fuel" has been used to refer to fuels such as coal, oil, and natural gas which are formed from the remains of plants and animals which have lain in the earth for millions of years. In the 1970s, a new word, "biofuel," began to be used to describe a different kind of fuel, one taken from more contemporary organic matter. These fuels include ethanol, which can be derived from such products as corn and sugarcane, and biodiesel, which can be formed from vegetable oils. These organic sources are reflected in the prefix, "bio-," meaning "life" or "living organisms or tissue." The prefix "bio-" was borrowed from the Greek "bios," meaning "mode of life."