Autotrophs are organisms that can produce their own food using inorganic substances. They primarily use sunlight or chemical energy to convert carbon dioxide and water into glucose through processes like photosynthesis or chemosynthesis. Common examples of autotrophs include plants, algae, and some bacteria. These organisms form the base of the food chain, providing energy for heterotrophs, which cannot produce their own food and rely on consuming other organisms. Autotrophs play a crucial role in ecosystems by contributing to oxygen production and serving as a primary energy source for various life forms.