Cable shielding is crucial to protect signal integrity by reducing electromagnetic interference (EMI) and radio frequency interference (RFI). Shielded cables prevent external noise from distorting data signals and protect the cable from emitting interference itself. Common shielding methods include foil shields, braid shields, and combination shields. Foil shields provide 100% coverage and excellent high-frequency protection but are less flexible. Braid shields offer mechanical strength and good shielding effectiveness at low frequencies while maintaining flexibility. Some cables combine foil and braid for superior shielding performance. Proper grounding of the shield is also critical to maximize EMI protection and minimize ground loops.