Common (script)

In Unicode, a script is a collection of letters and other written signs used to represent textual information in one or more writing systems. Some scripts support one and only one writing system and language, for example, Armenian. Other scripts support many different writing systems; for example, the Latin script supports English, French, German, Italian, Vietnamese, Latin itself, and several other languages. Some languages make use of multiple alternate writing systems, thus also use several scripts. In Turkish, the Arabic script was used before the 20th century, but transitioned to Latin in the early part of the 20th century. For a list of languages supported by each script see the list of languages by writing system. More or less complementary to scripts are symbols and Unicode control characters.

The unified diacritical characters and unified punctuation characters frequently have the "common" or "inherited" script property. However, the individual scripts often have their own punctuation and diacritics, so that many scripts include not only letters, but also diacritic and other marks, punctuation, numerals and even their own idiosyncratic symbols and space characters.

Unicode 9.0 defines 135 separate scripts, including 84 modern scripts and 51 ancient or historic scripts. More scripts are in the process for encoding or have been tentatively allocated for encoding in roadmaps.

When multiple languages make use of the same script, there are frequently some differences: particularly in diacritics and other marks. For example, Swedish and English both use the Latin script. However, Swedish includes the character ‘å’ (sometimes called a "Swedish O") while English has no such character. Nor does English make use of the diacritic combining circle above for any character. In general the languages sharing the same scripts share many of the same characters. Despite these peripheral differences in the Swedish and English writing systems they are said to use the same Latin script. So the Unicode abstraction of scripts is a basic organizing technique. The differences between different alphabets or writing systems remain and are supported through Unicode’s flexible scripts, combining marks and collation algorithms.

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