Language is at the heart of the learning process. We learn through language. Our knowledge about the world is constructed in language—the worlds of home and the community, the worlds of school subjects, the worlds of literature, the worlds of the workplace, and so on. It is through language that we interact with others and build our identities. Teachers’ explanations, classroom discussions, assessment of student achievement, and students’ understanding, composition, and evaluation of texts are all mediated through language. In this book, we will be exploring how an explicit understanding of how language works enables students to make informed choices in their use and understanding of texts.