Phonetics

Articulatory phonetics investigates and classifies speech sounds in terms of the way they are produced by the speech organs.

Acoustic phonetics is concerned with the physical properties of the sounds produced and their transmission through the air in terms of the study of physics.

Auditory phonetics is concerned with the perception and recognition of speech sounds by the human ear and brain.

Voicing is the vibration of the vocal cords.

If the velum, or soft palate, is lowered at the back of the throat to keep open the passage into the nasal cavity, air can escape through the nose at the same time as it also emerges from the mouth.

Aspiration is the audible breath which may accompany a sound's articulation.

Consonants are sounds produced by temporarily obstructing or restricting the airstream as it passes through the mouth.

Vowels are sounds produced without any obstruction or restriction of the airstream.

Articulator is any specific part of the vocal apparatus involved in the production of a speech sound

Place of articulation is a parameter referring to where in the vocal apparatus a sound is produced.

The airstream can be modified at eight places of articulation: glottis (glottal), pharynx (pharyngeal), uvula (uvular), velum (velar), palate (palatal), alveolus (alveolar), teeth (dental), and lips (labial).

A stop is a sound produced when the airflow is completely obstructed during speech.

A fricative is a sound produced when the airflow is forced through a narrow opening in the vocal tract so that noise produced by friction is created.

An affricate is a single but complex sound, beginning as a stop but releasing secondarily into a fricative.

An obstruent is a sound involving a constriction which impedes the flow of air through nose or mouth, as in stops, fricatives and affricates.

An approximant is a sound produced by two articulators approaching one another, but the degree of narrowing involved does not produce audible friction.

A liquid is a non-technical impressionistic expression indicating that the sound is "smooth" and "flows easily." Liquids (/r/ and /l/) share properties of both consonants and vowels: as in the articulation of certain consonants, the tongue blade is raised toward the alveolar ridge; as in the articulation of vowels, air is allowed to pass through the oral cavity without great friction.

Glides (/j/ and /w/) are vowel-like articulations that precede and follow true vowels.

The manner of articulation is a parameter referring to how the articulators achieve contact with or proximity to the places of articulation.