University of Notre Dame documents carbon nanotubes (CNTs), including their structure, properties, growth techniques, and applications. CNTs are tubular carbon structures just nanometers in diameter that can be metallic or semiconducting depending on their structure. They exhibit extraordinary properties including high strength and unique electronic behavior. Common growth methods are arc discharge, laser ablation, and chemical vapor deposition using metal catalysts. The growth mechanism involves carbon dissolving in catalytic nanoparticles and precipitating as tubes. Controlling the growth conditions is important for determining CNT structure and properties. CNTs show promise for applications in electronics, optics, and materials due to their desirable characteristics.