Phonic level of language is studied by two complementary disciplines_ phonetics and phonology.

1.Phonetics – deal with the material of speech itself.Speech sounds are studies from 3 differents point of view, which correspond with 3 main branches of phonetics.

1. Articulary phonetics – Studies speech sound from the speakre´s point of view in terms of the articulatory organs and processes involved.
2. Acoustic phonetics- studies speech sounds from the point of view of the transmission of the speaker´s output in terms of physical charakteristics/ wave form, intensity, periodicity, noise/
3. Auditory phonetics – studies speech sounds from the point of view of the hearer in terms of physiology and psychology of perciption.

Add1 * Articulary phonetics has a long tradition compared to other subdisciplines of phonetics. Phonetically it is possible to lasify speech sounds into 2 great classes- vocoids and contoids.
Vocoids- are those speech sounds which generally speaking have the following charakteristic : the air stream and usually the vocal cords are vibrating
Contoids- are those speech sounds which have the following charakteristic: the air stream is not allowed a completely free passage.
Most of the sounds called consonants in English belong to the class of the above defined contoids. They can be classified according to the following criteria:
a/ the kind of stricture i.e. manner of the articulation
b/ the place of articulation
c/ the opposition voiced- voiceless depending on the vibration of vocal cords
d/ whether sound will be oral or nasal

Out of number of consonant modification occuring in languages the most typical for English affects voiceless plosives/ p,t,k,/ at the beginning of syllable when followed by a streses vowel/ as in pin, kin, tin,until/
Vowel usually described based on frame of reference called Cardinal Vowel Scheme.
Cardinal vowels are not sounds of any particular language, they are artificial constructs. All english vowels are voiced.
In their classification 3 criteria are usually taken into account.
1/the duration of the sound- opossiotion short – long.
2/ the kind of opening made by lips- spread, neutral, rounded
3/the position of the highest part of the tongue- high –low, front-central-back, respectlively.

A Dipthong is a combination of two vowels produced one immediately after the other.