Carbon nanotubes (CNTs) are cylinder-shaped molecules made up of rolled-up single-layer carbon atom sheets (graphene). Single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCN) are the two main types of carbon nanotubes (MWCNT). Single-walled nanotubes (SWCNT) have a diameter of less than 1 nanometer (nm), while multi-walled nanotubes (MWCNT) have diameters of more than 100 nm and are made up of multiple concentrically interconnected nanotubes. Their length might range from a few micrometers to millimeters. Carbon nanotubes are one of the strongest materials known to man, with unique structural and electrical attributes that make them suitable for a wide range of applications.