This document provides an overview of ecology. It begins by defining ecology as the scientific study of interactions between organisms and their environments, with a focus on energy transfer. It then discusses key ecological terms like environment, organism, population, community, ecosystem, biosphere, habitat, and niche. The document also covers the abiotic and biotic factors that make up environments. It explains ecology's interdisciplinary nature and relationship to other sciences. Finally, it discusses important ecological concepts like biodiversity, climate change, levels of ecological organization, types of ecosystems and adaptations.