According to Hayes and Flower's (1980) model, the writer would have built, as an output of the Planning process (Cf. Chapter 1), a content plan. This plan, following communicative and eventually rhetorical intentions, lists an organised structure of the main themes or main ideas of the to-be-written text. However this content plan is just a general plan. It can only permit to plan the general text content and to keep the global coherence. It does not provide any detail about this content and, furthermore, any information about the future "linguistic and physic aspects' of the text, on paper or on a computer screen. In other words, if the Planning process organises and plans, it does not enable the effective composition and realisation of the text. Indeed, after the Planning process, the writer has to (1) elaborate the text content by developing each part of the plan that needs to be developed, and (2) translate this developed content into a linguistic form. It is in this way that Hayes and Flower (1980: 15) consider that "the function of the translating process is to take material from long term memory under the guidance ofthe writing plan and to transform it into acceptable written English sentences". The general definition of the Translating process they propose is underlined by the fact that these authors consider that the domain knowledge is not linguistic nor linear: "We assume that material in memory is stored as a proposition but not necessarily as language. By a proposition we understand a structure […] where concepts, relations and attributes are memory structure, perhaps complex networks or images, for which the writer mayor may not have names (p. 15)".