In this final chapter, some recent research topics are summarized, and some properties of materials are presented together with applications. Some very briefly presented topics are junctions of semiconductors and the transistor, the Klein paradox and minimal conductivity in graphene, examples of some two-dimensional topological materials, altermagnets, spintronics, giant magnetoresistance, heavy-fermion materials, unconventional superconductors, strongly correlated non-Fermi liquids, interface phases, quantum circuits and Majoranas, frustrated systems, spin ice and magnetic monopoles in condensed matter systems, and some other topics.