Screws are commonly used for what purpose in mechanical assembly?

Screws are primarily used to attach components together in mechanical assembly. Their threaded design allows them to create a strong connection between two or more parts, which can withstand various forces and loads. When a screw is driven into a material, the threads engage with the material, creating a secure hold. This functionality makes screws fundamental in a wide range of applications, from simple household items to complex machinery, ensuring that components remain fixed in their intended locations.

While other options may reference various functions in mechanical or engineering contexts, they do not pertain to the primary purpose of screws. For example, providing movement is typically the role of mechanical linkages or actuators, not screws. Reducing friction often involves lubricants or specific bearing designs, while creating insulation is primarily related to materials designed to prevent heat or electrical transfer. In summary, the use of screws for fastening components is a foundational aspect of assembly in mechanical engineering and product design.