water wiki:
>This article focuses on water as it is experienced in everyday life. See water (molecule) for information on the chemical and physical properties of pure water (H2O, hydrogen oxide). Water (from the Old English word wæter; c.f German "Wasser", from PIE *wod-or, "water") is a tasteless, odorless, and nearly colorless (it has a slight hint of blue) substance in its pure form that is essential to all known forms of life and is known also as the most universal solvent. Water is an abundant substance on Earth. It exists in many places and forms: mostly in the oceans and polar ice caps, but also as clouds, rain water, rivers, freshwater aquifers, and sea ice. On the planet, water is continuously moving through the cycle involving evaporation, precipitation, and runoff to the sea.
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Halftone wiki:
ftoning is a method of printing shades using a single color ink. By varying the size or density of dots, the eye can see a shade somewhere between the solid colour and the colour of the background paper. The effect has its limits, and when the dots get too small or spaced too far apart, the eye can start seeing individual dots again.
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