“An orthography is any method of mapping the sounds of a language onto a set of written symbols” (Miller, 1996: 41). Thus, the writing systems that developed historically have been logographic (Chinese hanzi and Japanese kanji), syllabic (Japanese kana), alphabetic (English), or some mixture of these. Syllabic and alphabetic scripts are phonetic, i.e. they provide characters to represent the sounds of the language. In this respect they may generally be grouped into a phonemically based writing system. In contrast, as logographic scripts are primarily morphemic, they may be grouped into a morphemically based writing system.
A theoretical goal of research on orthographic processing is to understand the common mechanisms for extracting the meaning of a word from visual patterns (graphic characters) that belong to several different orthographies. One pragmatic goal is to understand how people acquire the capacity for rapid and effortless reading as well as to understand the impairments that occur both developmentally and following brain injury (Iwata, 1984; Yamadori, 1998). Orthographic processing has also provided a way to explore broader theoretical issues concerning memory retrieval and knowledge representation in the mental lexicon; for example, subunits (module) and connectionist approaches to word recognition (Saito, 1997).
Much experimental information about orthographic processing is available for alphabetically written English words (Taft, 1991). However, to account for rules of orthographic processing, a closer examination of logographic (morphemically based) writing systems, as well as phonemically based ones, is necessary (Chen & Zhou, 1999).