By writing for interaction, I mean writing that is meant to be interactive for a reader, not simply in the sense that reading is an experience created by both writer and reader, but rather that the decisions made by the reader change what is read. That is, reading practices that enable responses from the text. It is one thing to write an email expecting a response and react to that response. It is another to write a book or other text for a broad audience that is designed to react to the reading choices made by individual members of that audience.
Via Nik Peachey