This document provides an overview of norm and deviation in stylistics. It discusses how deviation occurs when something departs from an established norm or convention. Deviations can happen at various linguistic levels, such as phonological, syntactic, or semantic levels. The document also categorizes different types of deviations, such as discourse deviation, semantic deviation, lexical deviation, and morphological deviation. It explains norms as regulators that control linguistic variants and how norms allow for flexible fluctuations in language.