A knurled screw is a type of screw that has a textured or grooved surface on its head or body. The knurling provides a better grip for the fingers or a tool, making it easier to tighten or loosen the screw without slipping.

Knurled screws are often used in applications where frequent adjustments or assembly and disassembly are required, such as in machinery, electronics, and various consumer products. They come in different materials, shapes, and sizes to fit specific applications and can have different types of heads, such as countersunk, pan, or round.