The 20th century is the century in which language was thematised. Philosophers and linguisticians occupied themselves with the phenomenon of "language" to a degree and in a breadth hitherto unknown. Language was not just regarded as a semiotic system (Saussure) but also as an organon (Bühler), organ (Chomsky), game (Wittgenstein), Letter (Lacan), script (Derrida), conversation (Gadmer), idiolect (Davidson), vocabulary (Rorty), sound form (Jakobson), reference (Quine), symbolisation (Waldron), meaning (Taylor), convention (Lewis) or paradoxical form (Luhmann). Thirty views of language are presented and classified under the aspects of sign, structure, representation, behaviour and medium.