What is the study of the differenet varieties of Catalan?
Catalan sociolinguistics studies the situation of Catalan in the world and the different varieties that this language presents. It is a subdiscipline of Catalan philology and other affine studies and has as an objective to analyse the relation between the Catalan language, the speakers and the close reality (including the one of other languages in contact).
Phonology also includes topics such as phonotactics (the phonological constraints on what sounds can appear in what positions in a given language) and phonological alternation (how the pronunciation of a sound changes through the application of phonological rules, sometimes in a given order which can be feeding or bleeding,) as well as prosody, the study of suprasegmentals and topics such as stress and intonation.