This chapter provides a comprehensive overview of morphology and its relevance to Chinese, situating it within broader theoretical and typological perspectives. It first introduces fundamental definitions of morphology and contrasts Chinese with alphabetic languages, emphasizing its morpho-syllabic system. The chapter then classifies Chinese morphological types, including compounds, derivations, and monomorphemic words, highlighting their structural and functional diversity. It further explores how morphological information is represented in the mental lexicon and processed in language comprehension, production, and development, drawing on psycholinguistic and neurolinguistic evidence. Key research issues, such as holistic versus decomposed processing, the role of morphological structure, and its interplay with orthography, phonology, and semantics, are critically reviewed. Finally, the chapter discusses lexical variables (e.g., word frequency, morpheme properties, and structural constraints) that modulate morphological processing, setting the stage for empirical investigations in subsequent chapters.