Ecosystem is a basic unit of nature that includes a community of organisms and their nonliving environment linked by biological, chemical, and physical processes.

Emissions reduction reporting is the calculating, tracking, and documenting of the greenhouse gas emissions that result directly from energy use and other operations of a building.

Emissivity is a ratio of radiation a surface gives off. Using products with low emissivity—for example white roofs rather than black roofs — reduces the heat island effect (see below) whereby urban landscapes become significantly warmer than surrounding rural landscapes.

Energy Star ® rated products meet the energy efficiency guidelines specified by the U.S. Environmental Protection Agency and the U.S. Department of Energy.