Chapter 2. Imaging teacher learning. From analog to digital Abstract Based on a review of the relevant literature, this chapter provides an overview of the field. It opens with a description of the development of analog towards digital video applications for teacher development. Then, a variety of digital applications is described and the specific affordances of digital video as a medium for teacher learning are identified. On this basis, different functions and features of digital video for teacher development are delineated and concepts and terminology introduced. Also, the main paradigms underlying the research reviewed are characterised. The main conclusion is that visual feedback can make teacher learning more effective by helping teachers relate thought and action. To conceptualise which conditions, activities and processes are involved, the Visual Teacher Learning model is introduced. This model also covers effects on pupil learning.