An autotroph is an organism that synthesizes food from inorganic substances by using chemical energy or light, according to the American Heritage Dictionary. Types of autotrophs include some kinds of bacteria, green plants and algae.
Autotrophs make their own food from substances present in their surroundings. Often, as is the case with algae, they make food for other creatures as well. Algae is a prime example of an autotroph that is a producer in the food chain. Not only does it feed itself, it produces food for other organisms, such as fish.
The word "autotroph" comes from the Greek words "auto," meaning "self" and "trophe," meaning "nutrition."
Some specific autotrophs include Venus fly traps, living rocks, green and purple sulfur bacteria and resurrection ferns.