Consonant

A writing system comprises a set of symbols, called a script, as well as the rules by which the script represents a particular language. The earliest writing appeared during the late 4th millennium BC. Throughout history, each independently invented writing system gradually emerged from a system of proto-writing, where a small number of ideographs were used in a manner incapable of fully encoding language, and thus lacking the ability to express a broad range of ideas.

Writing systems are generally classified according to how their symbols, called graphemes, relate to units of language. Phonetic writing systems – which include alphabets and syllabaries – use graphemes that correspond to sounds in the corresponding spoken language. Alphabets use graphemes called letters that generally correspond to spoken phonemes. They are typically divided into three sub-types: Pure alphabets use letters to represent both consonant and vowel sounds, abjads generally only use letters representing consonant sounds, and abugidas use letters representing consonant–vowel pairs. Syllabaries use graphemes called syllabograms that represent entire syllables or moras. By contrast, logographic (or morphographic) writing systems use graphemes that represent the units of meaning in a language, such as its words or morphemes. Alphabets typically use fewer than 100 distinct symbols, while syllabaries and logographies may use hundreds or thousands, respectively.

A syllable is a basic unit of organization within a sequence of speech sounds, such as within a word, typically defined by linguists as a nucleus (most often a vowel) with optional sounds before or after that nucleus (margins, which are most often consonants). In phonology and studies of languages, syllables are often considered the "building blocks" of words. They can influence the rhythm of a language: its prosody or poetic metre. Properties such as stress, tone, and reduplication operate on syllables and their parts. Speech can usually be divided up into a whole number of syllables: for example, the word ignite is made of two syllables: ig and nite. Most languages of the world use relatively simple syllable structures that often alternate between vowels and consonants.

Despite being present in virtually all human languages, syllables still have no precise definition that is valid for all known languages. A common criterion for finding syllable boundaries is native-speaker intuition, but individuals sometimes disagree on them.

In phonetics (a branch of linguistics), a phone is any distinct speech sound. It is any surface-level or unanalyzed sound of a language, the smallest identifiable unit occurring inside a stream of speech. In spoken human language, a phone is thus any vowel or consonant sound (or semivowel sound). In sign languages, a phone is the equivalent of a unit of gesture.

In linguistics, a segment is "any discrete unit that can be identified, either physically or auditorily, in the stream of speech". The term is most used in phonetics and phonology to refer to the smallest elements in a language, and this usage can be synonymous with the term phone.

In spoken languages, segments will typically be grouped into consonants and vowels, but the term can be applied to any minimal unit of a linear sequence meaningful to the given field of analysis, such as a mora or a syllable in prosodic phonology, a morpheme in morphology, or a chereme in sign language analysis.

In articulatory phonetics, the place of articulation (also point of articulation) of a consonant is an approximate location along the vocal tract where its production occurs. It is a point where a constriction is made between an active and a passive articulator. Active articulators are organs capable of voluntary movement which create the constriction, while passive articulators are so called because they are normally fixed and are the parts with which an active articulator makes contact. Along with the manner of articulation and phonation, the place of articulation gives the consonant its distinctive sound.

Since vowels are produced with an open vocal tract, the point where their production occurs cannot be easily determined. Therefore, they are not described in terms of a place of articulation but by the relative positions in vowel space. This is mostly dependent on their formant frequencies and less on the specific tongue position and lip rounding.

In articulatory phonetics, the manner of articulation is the configuration and interaction of the articulators (speech organs such as the tongue, lips, and palate) when making a speech sound. One parameter of manner is stricture, that is, how closely the speech organs approach one another. Others include those involved in the r-like sounds (taps and trills), and the sibilancy of fricatives.

The concept of manner is mainly used in the discussion of consonants, although the movement of the articulators will also greatly alter the resonant properties of the vocal tract, thereby changing the formant structure of speech sounds that is crucial for the identification of vowels. For consonants, the place of articulation and the degree of phonation or voicing are considered separately from manner, as being independent parameters. Homorganic consonants, which have the same place of articulation, may have different manners of articulation. Often nasality and laterality are included in manner, but some phoneticians, such as Peter Ladefoged, consider them to be independent.

While many languages have numerous dialects that differ in phonology, contemporary spoken Arabic is more properly described as a continuum of varieties. This article deals primarily with Modern Standard Arabic (MSA), which is the standard variety shared by educated speakers throughout Arabic-speaking regions. MSA is used in writing in formal print media and orally in newscasts, speeches and formal declarations of numerous types.

Modern Standard Arabic has 28 consonant phonemes and 6 vowel phonemes, with four "emphatic" (pharyngealized) consonants that contrast with their non-emphatic counterparts. Some of these phonemes have coalesced in the various modern dialects, while new phonemes have been introduced through borrowing or phonemic splits. A "phonemic quality of length" applies to consonants as well as vowels.