Carbon nanotubes (CNTs) and graphene are two of the most prominent carbon-based nanomaterials, renowned for their exceptional mechanical strength, electrical conductivity, thermal stability, and large surface area. Carbon nanotubes, which exist as single-walled or multi-walled cylindrical structures, offer remarkable tensile strength and are widely used in electronics, nanocomposites, and drug delivery systems. Graphene, a single layer of sp²-bonded carbon atoms arranged in a two-dimensional honeycomb lattice, exhibits extraordinary electronic properties, high carrier mobility, and optical transparency. Both materials have revolutionized fields such as nanoelectronics, energy storage, flexible devices, and biosensing. Ongoing research focuses on scalable synthesis, functionalization, and integration of CNTs and graphene into advanced technologies, making them central to the future of nanoscience and materials engineering.