1.1. Explaining sound patterns

Phonology is the study of sound patterns of the world's languages. In all spoken languages, we find sound patterns characterizing the composition of words and phrases. These patterns include overall properties of contrastive sound inventories (e.g. vowel inventories, consonant inventories, tone inventories), as well as patterns determining the distribution of sounds or contrastive features of sounds (stress, tone, length, voicing, place of articulation, etc.), and their variable realization in different contexts (alternations). A speaker's implicit knowledge of these patterns is often evident in their extension to novel items and in experiments probing phonological well-formedness. This implicit knowledge – its content, formalization, and representation, – is the central focus of modern theoretical phonology, including generative phonology and many of its derivatives (natural phonology, government phonology, dependency phonology, optimality theory).