This part of ISO 9241 applies to physical input devices for interactive systems. It provides guidance based on ergonomic factors for the following devices: keyboards, mice, pucks, joysticks, trackballs, trackpads, tablets and overlays, touch sensitive screens, styli, and light pens, voice controlled devices, gesture controlled devices. This part of ISO 9241 gives guidance on the design of these devices so that the capabilities and limitations of users are considered. The guidance includes generic design criteria for physical input devices as well as specific design criteria for each type of device. Requirements for the design of products are given either as a result of context-free considerations (e.g. "The contrast of key legends shall be greater than ...") or need to be determined in consideration of the specified design criteria for the intended use.