Information Structure and Thematisation

Another resource that contributes to giving texture to a text is its thematic structure. We are referring to the organization of information in a  text as a whole. Two points are very important: we are not treating a text as mere transmission of data but as a communicative event. No texts can be claimed to be purely informative, in fact also gossip or TV news are not only informative but they have also social or professional function.
The second point is the fact that the options available to a writer for arranging information in a text are not arbitrary since they serve the communicative purpose of making writers' intentions and the discourse more readily comprehensible. The informations contained in a text are arranged in such a way as to carry the writer's message forward and to focus the reader's attention on some elements rather than on others.
The tendency to arrange sentences in such a way as to draw attention to what is communicatively more important is known as THEMATISATION and it is centred around the concepts of Theme and Rheme and the related notions of GIVEN and NEW INFORMATION.
The choice of clause themes and rhemes ans their sequencing are not random occurrences but depend very much on discourse genres and rhetorical purposes.
The importance of the Theme is that is identifies what the message of the clause concerns and what should be highlighted. Its choice is important for both speaker and  hearer as it represents the angle from which the message is projected. The initial element acts as signal to the hearer, directing expectations regarding the structure that is likely to follow. The way Theme and Rheme are used and re-used ina  text is related to the speaker/writer's overall text-plan and audience orientation.