Scanning electron micrograph (SEM) of Carbon nanotubes. Carbon nanotubes are rolled sheets of carbon atoms that form cylinders. They are structurally related to fullerenes cages of carbon atoms discovered in 1985. Nanotubes are grown by several laboratory techniques and they are just a few nanometres in diameter and several microns long. In the field of nanotechnology the tiny size of the tubes may yield useful electrical components. Nanotubes have a very broad range of electronic, thermal, and structural properties that change depending on the different physical parameters of nanotubes. Single, cylindrical wall nanotubes (SWNTs) and complex, multiple wall nanotubes (MWNTs) can be formed in to produce nanofibers and nanoelectronic components. Magnification: x40, 000 when shortest axis printed at 25 millimetres.