A material that has at least one dimension of 1—100 nanometres, whether naturally occurring or artificially produced, to achieve specific properties. Nanomaterials may have different physical or chemical properties than a material with the same chemical composition but larger dimensions. This is due to quantum effects, which occur at nanometer dimensions. One of the most well-known nanomaterials are carbon nanotubes. Nanomaterials have a wide range of applications, ranging from medicine, where engineered nanoparticles help deliver drugs to specific locations in the body, self-cleaning surfaces, to making flexible solar cells.