Of Grammatology by French philosopher and literary theorist Jacques Derrida (1930–2004) is a work of nonfiction in the area of philosophy sometimes known as "critical theory" or "theory." It was originally composed as a doctoral thesis and first published in 1967. In this work, Derrida explores ideas about the nature of language and argues that the western philosophical tradition is based on misconceptions about language. Derrida advances in this work a new theory about language and textuality that is called "deconstruction." Because this is a work of philosophy, it does not have characters per se. In his critique of western philosophy, though, Derrida does discuss many earlier thinkers. As Derrida presumes familiarity with these thinkers rather than explaining or summarizing them, familiarity with their work is important for reading Derrida.

The first major influences on Of Grammatology are thinkers Derrida's studied or studied with in graduate school. Derrida wrote extensively about German philosopher Husserl (1859–1938), the founder of a school known as phenomenology, and was especially interested in Husserl's phenomenological approach to time in relationship to presence. Although Derrida denies that French phenomenologist Merleau-Ponty was a major influence on his work, many scholars see parallels between their ideas. Derrida also discusses the German idealist philosopher Georg Wilhelm Friedrich Hegel (1770–1831) frequently, especially in his critique of metaphysics. Derrida actually participated in a seminar with Michel Foucault (1926–1984), whose work he criticized as misunderstanding the Enlightenment. Derrida was also influenced by German philosopher Martin Heidegger's (1889–1976) treatment of being and reading of early Greek philosophy and the theories of alterity advanced by French Jewish philosopher Emmanuel Levinas (1906–1995). Nietzsche, Saussure, and Freud were also important influences.

Plato looms large in Derrida, taking on almost the role of an antagonist. Derrida sees Plato as a figure who was foundational in developing metaphysics and the logocentric shape of western philosophy. Derrida disagrees with what he sees as a Platonic privileging of speech over writing and also tries to collapse the binary oppositions of Platonic dialectic and critique the theory of forms.

Significant sections of On Grammatology are devoted to analysis of anthropologist Claude Lévi-Strauss’s Tristes Tropiques and interpret it quite broadly (or some argue, inaccurately) to associate written language with violence. Derrida also devotes considerable space to exegesis of Jean-Jacques Rousseau, especially the Essay on the Origin of Languages.