In all communication, in all domains of the social world, meanings are made as ensembles which draw on different modes: gesture, speech, 3D objects, image, writing, gaze, music, posture and positioning, actions of many kinds. The division of semiotic labour of modes shown in this example is specific to a particular culture, and to a specific period. Fifty years earlier, the division of semiotic labour would have been much more heavily weighted towards writing. The interest of the learner shapes attention to that which is to be learned, leading to selection from what is presented in the world; interest determining the focus on what is to be engaged with, selected and transformed, in learning. From a social semiotic perspective, the notions of explicitness and implicitness are not intrinsic properties of forms of representation: they are social and cultural categories. In Western societies, so called, these notions have had far-reaching effects on mainstream and dominant conceptions of teaching, learning and assessment.