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A Unicode font (also known as font and Unicode typeface) is a computer font that contains a wide range of characters, letters, digits, glyphs, symbols, ideograms, logograms, etc., which are collectively mapped into the standard Universal Character Set, derived from many different languages and scripts from around the world. Unlike most conventional computer fonts, which are specific to a particular language or legacy character set and contain only a small subset of the UCS characters, these fonts attempt to include many thousands of possible glyphs, so that they can be used as a single typeface across multilingual documents. ==Background== The Unicode standard does not specify or create the font (typeface), a collection of graphical shapes called glyphs, itself. Rather, it defines the abstract characters as a specific number (known as a ''codepoint'') and also defines the required changes of shape depending on the context the glyph is used in (e.g., combining characters, precomposed characters and letter-diacritic combinations). The choice of font, which governs how the abstract UCS characters are converted into a bitmap or vector output that can be viewed on a screen or printed, is left up to the user. If a font is chosen which does not contain a glyph for a codepoint used in the document, typically a question mark, a box, or some other substitute character is displayed. Computer fonts use various techniques to display characters or glyphs. A bitmap font contains a grid of dots known as pixels forming an image of each glyph in each face and size. Outline fonts (also known as vector fonts) use drawing instructions or mathematical formulæ to describe each glyph. Stroke fonts use a series of specified lines (for the glyph's border) and additional information to define the ''profile'', or ''size'' and shape of the line in a specific face and size, which together describe the appearance of the glyph. Many fonts have kerning pairs which implements better spacing in between the characters. Fonts also include embedded special orthographic rules to output certain combinations of letterforms (an alternative symbols for the same letter) be combined into special ligature forms (mixed characters). Operating system and web browser (user agent) use a font to display text on the screen or print media and can be programmed to use those embedded rules. Alternatively they may use external script-shaping technologies (rendering technology or “smart font” engine) and they can also be programmed to use either a large Unicode font, or use multiple different fonts for different characters or languages. No single "Unicode font" includes all the characters defined in the present revision of ISO 10646 (Unicode) standard, as it is continually adding more & more languages and characters. As a result, font developers and foundries are also incorporating those new characters in newer version or revision of a font, and correcting their previous errors if there were any. The UCS has over 1.1 million code points, but only the first 65,536 (the Plane 0: Basic Multilingual Plane, or BMP) had entered into common use before 2000. (See the Unicode planes article for more information on other planes, including Plane 1: SMP, Plane 2: SIP, Plane 14: SSP, Plane 15 and 16: reserved for PUA.) The first Unicode fonts (with very large character set, and supporting many Unicode blocks) were Lucida Sans Unicode (released March 1993), Unihan font (1993), and Everson Mono (1995). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Unicode font」の詳細全文を読む スポンサード リンク
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