U+1D583 Mathematical Bold Fraktur Capital X

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Fraktur (German: [fʁakˈtuːɐ̯] ) is a calligraphic hand of the Latin alphabet and any of several blackletter typefaces derived from this hand. It is designed such that the beginnings and ends of the individual strokes that make up each letter will be clearly visible, and often emphasized; in this way it is often contrasted with the curves of the Antiqua (common) typefaces where the letters are designed to flow and strokes connect together in a continuous fashion. The word "Fraktur" derives from Latin frāctūra ("a break"), built from frāctus, passive participle of frangere ("to break"), which is also the root for the English word "fracture". In non-professional contexts, the term "Fraktur" is sometimes misused to refer to all blackletter typefaces – while Fraktur typefaces do fall under that category, not all blackletter typefaces exhibit the Fraktur characteristics described above.

Fraktur was often characterized as "the German typeface", as it remained popular in Germany and much of Eastern Europe far longer than elsewhere. In Germany, utilizing more modern typefaces would prove controversial until 1941, when the Nazi government rendered any transition involuntary by banning the use of Fraktur typefaces.