An organism classified as a producer creates organic matter from inorganic substances by converting energy from the sun (photosynthesis) or chemical reactions (chemosynthesis) into biomass that other organisms (consumers) can use.  These conversions supply energy and matter to the rest of the ecosystem. Producers thus form the base of most food webs. Common examples of producers: plants, algae, cyanobacteria, and some bacteria that perform chemosynthesis.