Here's why:

* Autotroph comes from the Greek words "autos" (self) and "trophe" (nourishment).

* Autotrophs use energy from the environment, like sunlight or chemical reactions, to convert inorganic compounds (like carbon dioxide and water) into organic compounds (like sugars).

* This process is called photosynthesis (for sunlight) or chemosynthesis (for chemical reactions).

Examples of autotrophs include plants, algae, and some bacteria.