Typographic measure system, used in the North America and the United Kingdom. Invented in 1879 by Nelson Hawks. In that system type and lines are measured in points and picas. One point is equal to 0,35146 mm (appr. 1/72 of inch). One pica is equal to 12 points. In the 1980s, Adobe introduced PostScript and corrected the length of point. The PostScript point is precisely 1/72 of inch (0,35278 mm). Text processors and typographic software used PostScript point by default. Therefore that system became de facto a world typographic standard.
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