This is the first book devoted to nanotubes and nanosheets made of boron nitride (BN). It shows how the properties of BN nanotubes and nanosheets have led to many exciting applications where carbon (C) materials cannot be used, including high-temperature metal-ceramic-based composites, substrates for graphene and other semiconducting layers in electronic devices, reusable absorbents for oil and other contaminants, dry solid lubricants, and biomedical applications. The book also covers C and other nanotubes and nanosheets to give readers a broad view of the latest nanomaterials research.