Hue is one of the main properties of a color, defined technically (in the CIECAM02 model), as "the degree to which a stimulus can be described as similar to or different from stimuli that are described as red, green, blue, and yellow," (the unique hues). The other main correlatives of color appearance are colorfulness, chroma, saturation, lightness, and brightness.
Usually, colors with the same hue are distinguished with adjectives referring to their lightness and/or chroma, such as with "light blue", "pastel blue", "vivid blue". Exceptions include brown, which is a dark orange, and pink, a light red with reduced chroma.
In painting color theory, a hue refers to a pure color—one without tint or shade (added white or black pigment, respectively). A hue is an element of the color wheel. Hues are first processed in the brain in areas in the extended V4 called globs.
A natural landscape is a landscape that is unaffected by human activity. A natural landscape is intact when all living and nonliving elements are free to move and change. The nonliving elements distinguish a natural landscape from a wilderness. A wilderness includes areas within which natural processes operate without human interference, but a wilderness must contain life. As implied, a natural landscape may contain either the living or nonliving or both. In his extensive travels in South America, Alexander von Humbolt became the first to conceptualize a natural landscape. Some have described a transition of a pristine landscape state to a humanized landscape state—which includes the human-modified landscape, the primeval landscape, the ancient landscape, the undisturbed wilderness and the managed landscape. The natural landscape is a place under the current control of natural forces and free of the control of people for an extended period of time.