A nut is a crucial mechanical fastener consisting of a box-shaped piece that is threaded internally, designed to be secured onto a threaded rod or bolt. Its primary function is to transmit tension and compression forces, thereby providing a rigid joint between two or more components. Various types of nuts exist, including hexagonal, square, and specialized designs, each optimized for different applications and load requirements. By tightening a nut onto a compatible thread, the structural integrity of assemblies is achieved through controlled clamping force, making them indispensable components in fields ranging from construction and automotive engineering to machinery assembly.