The discovery of graphene, a 2D layered form of carbon, once caused a paradigm shift in science and technology like no other. As this wonder material drew attention from material scientists around the world, it spurred research on other materials that were structurally similar, such as "van der Waals materials," which comprise strongly-bonded 2D atomic layers that are held together by weak interlayer interactions called "van der Waals forces." These materials quickly caught on because they were highly conducive to structural modifications, such as stacking, twisting, and insertion of foreign molecules between layers, which gave them interesting physical properties with several practical applications.