texture wiki:
ture is the properties held and sensations caused by the external surface of objects received through the sense of touch. Texture is sometimes used to describe the feel of non-tactile sensations. Texture can also be termed as a pattern that has been scaled down (especially in case of two dimensional non-tactile textures) where the individual elements that go on to make the pattern are not distinguishable.
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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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