Nature, in the broadest sense, is the natural, physical, or material world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are part of nature, human activity is often understood as a separate category from other natural phenomena.
Within the various uses of the word today, "nature" often refers to geology and wildlife.
Nature can refer to the general realm of living plants and animals, and
in some cases to the processes associated with inanimate objects—the
way that particular types of things exist and change of their own
accord, such as the weather and geology of the Earth. It is often taken to mean the "natural environment" or wilderness—wild
animals, rocks, forest, and in general those things that have not been
substantially altered by human intervention, or which persist despite
human intervention. For example, manufactured objects and human
interaction generally are not considered part of nature, unless
qualified as, for example, "human nature" or "the whole of nature". This
more traditional concept of natural things that can still be found
today implies a distinction between the natural and the artificial, with
the artificial being understood as that which has been brought into
being by a human consciousness or a human mind. Depending on the particular context, the term "natural" might also be distinguished from the unnatural or the supernatural.
Earth is the only planet known to support life, and its natural features are the subject of many fields of scientific research. Within the solar system, it is third closest to the sun; it is the largest terrestrial planet and the fifth largest overall. Its most prominent climatic features are its two large polar regions, two relatively narrow temperate zones, and a wide equatorial tropical to subtropical region. Precipitation
varies widely with location, from several metres of water per year to
less than a millimetre. 71 percent of the Earth's surface is covered by
salt-water oceans. The remainder consists of continents and islands,
with most of the inhabited land in the Northern Hemisphere.
