group of cows eating grass under blue sky

>For alternative meanings, see nature (disambiguation). Nature (also called the material world, the material universe, the natural world, and the natural universe) is all matter and energy, especially in its essential form. Nature is the subject of scientific study, and the history of the concept is linked to the history of science. The English word derives from a Latin term, natura, which was in turn a translation of a Greek term, physis (φύσις). Natura is related to the Latin words relating to "birth", while physis relates to Greek words relating to "growth". In scale, "nature" includes everything from the universal to the subatomic. This includes all things animal, plant, and mineral; all natural resources and events (hurricanes, tornadoes, earthquakes). It also includes the behaviour of living animals, and processes associated with inanimate objects - the "way" that things change. See more at Wikipedia.org...

>For other uses, see Sky (disambiguation). The sky is (roughly) that part of the atmosphere or of outer space visible from the surface of the earth (or any other planet; see Skies of other planets).). Birds, airplanes, and kites are often considered to fly in the sky. It is difficult to define precisely for several reasons. During daylight the sky has the appearance of an opaque blue surface, but this is the result of the air refracting sunlight. There is no "blue object" above the earth in any normal sense, so it is hard to say what object the sky is. The sky is thus sometimes defined as the denser gaseous zone of a planet's atmosphere. At night the sky has the appearance of a black surface or region scattered with stars. But if we then say that the sky is the entire visible universe, it would not be the same thing we see during the day. See more at Wikipedia.org...