➀ This article reviews advancements in nanotechnology, focusing on material encapsulation within nanotubes, highlighting the importance of understanding atomic and molecular interactions within nanotubes and their influence on the performance of the resulting nanostructures. ➁ The review discusses how confinement within nanotubes alters material properties and examines potential applications in electronics, energy storage, and drug delivery. ➂ It also addresses challenges such as achieving uniform material loading and preventing aggregation during encapsulation.