Energy flows through an ecosystem in a complex network of interactions known as a food chain or food web. It begins with producers, such as plants that convert sunlight into chemical energy through photosynthesis. This energy is then transferred to consumers, including herbivores and carnivores, as they feed on plants and other animals. Decomposers, like fungi and bacteria, also play a crucial role by breaking down dead organic matter, returning nutrients to the soil and allowing the cycle to continue. This energy transfer is often represented using trophic levels.