Spoken and Sign Language Writing Systems: A Comprehensive Typology

Writing systems for spoken languages have traditionally been classified into types such as morphographic, syllabic, or alphabetic. However, these frameworks systematically omit notation systems developed for sign languages. To address this gap,this thesis proposes a unified typology based on the functional relationship between graphic symbols and phonological units. A systematic review of phonological structures in both spoken and signed languages clarifies the definitions of phonetic features, phonemes, syllables, morae, and mor- phemes. Subsequently, a selection of spoken language writing systems and sign language notation systems is described. Comparative analysis demonstrates that, despite substantial differences in inventory size and representational granularity, all examined sign language writing systems map individual symbols to subsegmental phonological components rather than to whole signs. Building on five foundational typologies, the proposed framework distinguishes morphographic from phonographic writing systems, then subdivides phonographic systems into polysegmental, segmental, and subsegmental types, with subcategories defined by the specific phonological units represented (e.g., /C/, /CV/, /CVC/). This typology resolves prior ambiguities in the contested classification of spoken language writing systems and, through its explicit inclusion of subsegmental systems, accommodates both historical feature-based transcription systems and all surveyed sign-language writing systems. Consequently, it unifies sign language and spoken language writing systems within a single coherent typological framework.