List of writing systems

Writing systems are used to record human language, and may be classified according to certain common features.
The usual name of the script is given first; the name of the languages in which the script is written follows (in brackets), particularly in the case where the language name differs from the script name. Other informative or qualifying annotations for the script may also be provided.
Ideographic scripts (in which graphemes are ideograms representing concepts or ideas rather than a specific word in a language) and pictographic scripts (in which the graphemes are iconic pictures) are not thought to be able to express all that can be communicated by language, as argued by the linguists John DeFrancis and J. Marshall Unger. Essentially, they postulate that no true writing system can be completely pictographic or ideographic; it must be able to refer directly to a language in order to have the full expressive capacity of a language. Unger disputes claims made on behalf of Blissymbols in his 2004 book Ideogram.
Although a few pictographic or ideographic scripts exist today, there is no single way to read them because there is no one-to-one correspondence between symbol and language. Hieroglyphs were commonly thought to be ideographic before they were translated, and to this day, Chinese is often erroneously said to be ideographic. In some cases of ideographic scripts, only the author of a text can read it with any certainty, and it may be said that they are interpreted rather than read. Such scripts often work best as mnemonic aids for oral texts or as outlines that will be fleshed out in speech.
There are also symbol systems used to represent things other than language:
In logographic writing systems, glyphs represent words or morphemes (meaningful components of words, as in mean-ing-ful) rather than phonetic elements.
No logographic script is composed solely of logograms. All contain graphemes that represent phonetic (sound-based) elements as well. These phonetic elements may be used on their own (to represent, for example, grammatical inflections or foreign words), or may serve as phonetic complements to a logogram (used to specify the sound of a logogram that might otherwise represent more than one word). In the case of Chinese, the phonetic element is built into the logogram itself; in Egyptian and Mayan, many glyphs are purely phonetic, whereas others function as either logograms or phonetic elements, depending on context. For this reason, many such scripts may be more properly referred to as logosyllabic or complex scripts; the terminology used is largely a product of custom in the field, and is to an extent arbitrary.
In a syllabary, graphemes represent syllables or moras. (The 19th-century term syllabics usually referred to abugidas rather than true syllabaries.)
In most of these systems, some consonant-vowel combinations are written as syllables, but others are written as consonant plus vowel. In the case of Old Persian, all vowels were written regardless, so it was effectively a true alphabet despite its syllabic component. In Japanese a similar system plays a minor role in foreign borrowings; for example, [tu] is written [to]+[u], and [ti] as [te]+[i]. Paleohispanic semi-syllabaries behaved as a syllabary for the stop consonants and as an alphabet for the rest of consonants and vowels.
The Tartessian or Southwestern script is typologically intermediate between a pure alphabet and the Paleohispanic full semi-syllabaries. Although the letter used to write a stop consonant was determined by the following vowel, as in a full semi-syllabary, the following vowel was also written, as in an alphabet. Some scholars treat Tartessian as a redundant semi-syllabary, others treat it as a redundant alphabet. Other scripts, such as Bopomofo, are semi-syllabic in a different sense: they transcribe half syllables. That is, they have letters for syllable onsets and rimes (kan = "k-an") rather than for consonants and vowels (kan = "k-a-n").
A segmental script has graphemes which represent the phonemes (basic unit of sound) of a language.
Note that there need not be (and rarely is) a one-to-one correspondence between the graphemes of the script and the phonemes of a language. A phoneme may be represented only by some combination or string of graphemes, the same phoneme may be represented by more than one distinct grapheme, the same grapheme may stand for more than one phoneme, or some combination of all of the above.
Segmental scripts may be further divided according to the types of phonemes they typically record:
An abjad is a segmental script containing symbols for consonants only, or where vowels are optionally written with diacritics ("pointing") or only written word-initially.
A true alphabet contains separate letters (not diacritic marks) for both consonants and vowels.
Linear alphabets are composed of lines on a surface, such as ink on paper.
A featural script has elements that indicate the components of articulation, such as bilabial consonants, fricatives, or back vowels. Scripts differ in how many features they indicate.
Manual alphabets are frequently found as parts of sign languages. They are not used for writing per se, but for spelling out words while signing.
These are other alphabets composed of something other than lines on a surface.
An abugida, or alphasyllabary, is a segmental script in which vowel sounds are denoted by diacritical marks or other systematic modification of the consonants. Generally, however, if a single letter is understood to have an inherent unwritten vowel, and only vowels other than this are written, then the system is classified as an abugida regardless of whether the vowels look like diacritics or full letters. The vast majority of abugidas are found from India to Southeast Asia and belong historically to the Brāhmī family, however the term is derived from the first characters of the abugida in Ge'ez: አ (a) ቡ (bu) ጊ (gi) ዳ (da) — (compare with alphabet). Unlike abjads, the diacritical marks and systemic modifications of the consonants are not optional.
In at least one abugida, not only the vowel but any syllable-final consonant is written with a diacritic. That is, if representing [o] with an under-ring, and final [k] with an over-cross, [sok] would be written as s̥̽.
In a few abugidas, the vowels are basic, and the consonants secondary. If no consonant is written in Pahawh Hmong, it is understood to be /k/; consonants are written after the vowel they precede in speech. In Japanese Braille, the vowels but not the consonants have independent status, and it is the vowels which are modified when the consonant is y or w.
The following list contains writing systems that are in active use by a population of at least 50,000.
These systems have not been deciphered. In some cases, such as Meroitic, the sound values of the glyphs are known, but the texts still cannot be read because the language is not understood. Several of these systems, such as Isthmian script and Indus script, are claimed to have been deciphered, but these claims have not been confirmed by independent researchers. In many cases it is doubtful that they are actually writing. The Vinča symbols appear to be proto-writing, and quipu may have recorded only numerical information. There are doubts that the Indus script is writing, and the Phaistos Disc has so little content or context that its nature is undetermined.
Comparatively recent manuscripts and other texts written in undeciphered (and often unidentified) writing systems; some of these may represent ciphers of known languages or hoaxes.
This section lists alphabets used to transcribe phonetic or phonemic sound; not to be confused with spelling alphabets like the ICAO spelling alphabet. Some of these are used for transcription purposes by linguists; others are pedagogical in nature or intended as general orthographic reforms.
Alphabets may exist in forms other than visible symbols on a surface. Some of these are:
See List of constructed scripts for an expanded version of this table.