From the outset of the use of digital technology in mathematics education, researchers focused on interactions between the tools and mathematical knowledge, exploring the ways the tool mediates knowledge and how, in turn, this mediation impacts the knowledge itself. This question remains topical in the context of a rapid development of digital technology and resources for mathematics teaching and learning and is central in the chapters of this section. The chapters in this section address three themes. The first theme explores how teaching and learning of “traditional” mathematics domains, such as arithmetic, algebra and functions, geometry, mathematical modeling, and statistics, can be approached differently with the recourse to digital resources. The second theme highlights new content that has entered mathematics curricula in relation to digital technology and resources, in particular computational thinking and programming. The third theme is devoted to emergent technologies – augmented and virtual reality, touch screen technology, robots – to highlight their affordances for mathematics teaching and learning and to showcase their use in mathematics classes. Finally, directions for future research concerning digital resources and mathematical content are outlined.