grammatology

n. study of writing systems, science of graphic script systems

Grammatology is a term coined by the  linguist Ignace Gelb in 1952 to refer to the scientific study of writing systems or scripts. It includes the typology of scripts, the analysis of the structural properties of scripts, and the relationship between written and spoken language. In its broadest sense, some scholars also include the study of literacy in grammatology.
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Derrida's term for the science of writing (in his sense of "writing").