Template:Unicode scripts In Unicode, a script is an abstract coherent and unified writing system supporting one or more concrete writing systems which in turn support the written forms of one or more languages. For example the Latin script supports alphabets such as: English, French, Vietnamese and many others. Some scripts support one and only one writing system and language, for example: Armenian. Other scripts, like Latin, support many different writing systems: English, French, German, Italian, and Latin to name just some of the alphabets supported by the Latin script. Some languages also make use of multiple alternate writing systems. Turkish, for example, used Arabic script before the 20th century and 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.
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.
While all characters have the property of belonging to a script, many characters, such as symbols, indicate “common” or “inherited” for their script property. 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 many scripts include not only letters, but also diacritic and other marks, punctuation, numerals and even their own idiosyncratic symbols and space characters.
Unicode already includes over 60 scripts supporting hundreds or even thousands of languages throughout the World. Unicode is actively working on many more as indicated by its roadmap.
Writing system
Writing system is sometimes treated as a synonym for script. However it also can be used as the specific concrete writing system supported by a script. For example the Vietnamese writing system is supported by the Latin script. Most writing systems can be broadly divided into several categories: logographic, syllabic, alphabetic (or segmental), abugida, abjad and featural; however, all features of any of these may be found in any given writing system in varying proportions, often making it difficult to purely categorize a system. The term complex system is sometimes used to describe those where the admixture makes classification problematic.
| Type of writing system | What each symbol represents | Example |
|---|---|---|
| Logographic | morpheme | Chinese characters |
| Syllabic | syllable | Japanese kana |
| Alphabetic | phoneme (consonant or vowel) | Latin alphabet |
| Abugida | phoneme (consonant+vowel) | Indian Devanāgarī |
| Abjad | phoneme (consonant) | Arabic alphabet |
| Featural | phonetic feature | Korean hangul |
See also: phonemic and phonetic orthography.
Unicode supports all of these types of writing systems through its numerous scripts. Unicode also adds further properties to characters to help differentiate the various characters and the ways they behave within Unicode text processing algorithms.
Character categories within scripts
Template:UCS characters Unicode provides a general category property for each character. So in addition to belonging to a script every character also has a general category. Typically scripts include letter characters including: uppercase letters, lowercase letter and modifier letters. Some characters are considered titlecase letters for a few precomposed ligatures such as Dz (U+01F2). Such titlecase ligatures are all in the Latin and Greek scripts and are all compatibility characters and therefore Unicode discourages their use by authors. Its unlikely newt titlecase letters will be added in the future.
Most writing systems do not differentiate between uppercase and lowercase letters. For those scripts all letters are categorized as “other letter” or “modifier letter”. Ideographs such as Unihan ideographs are also categorized as “other letters”. A few scripts do differentiate between uppercase and lowercase however: Latin, Cyrillic, Greek, Armenian, Georgian, and Deseret. Even for these scripts there are some letters that are nether uppercase nor lowercase.
Scripts can also contain any other general category character such as marks (diacritic and otherwise), numbers (numerals), punctuation, separators (word separators such as spaces), symbols and non-graphical format characters. These are included in a particular script when they are unique to that scripts. Other such characters are generally unified and included in the punctuation or diacritic blocks. However, the bulk of characters in any script (other than the common and inherited scripts) are letters.
Common and inherited script
Strictly speaking, Unicode assigns every character in the UCS to a script (one and only one). However, many characters — those that are not part of a formal natural language writing system or are unified across many writing systems — belong to the common script. Included in the common script are most numerals, most symbols including music notation, currency symbols and so forth. In addition, many diacritics and non-spacing combining characters are assigned to the inherited script. For these characters their script membership depends on the script of the character with which they combine.