An ecosystem refers to a dynamic community of living organisms interacting with each other and their physical environment as a functional unit. Within an ecosystem, organisms exchange energy, nutrients, and information, resulting in a balance that sustains life in a specific habitat. Ecosystems include biotic components like producers, consumers, and decomposers, as well as abiotic factors like climate and soil. Energy and nutrients cycle through the ecosystem via processes like photosynthesis, respiration, and decomposition, while species fill different trophic levels in the food web. Ecosystems strive for balance and resilience to withstand disturbances through interactions and processes among their living and non-living elements.