The type of pointer or controller input device should be appropriate for the tasks anticipated for its use.
Additional Information: Table 11-6 identifies the appropriate use of various control and input devices. ISO Standard 9241-9, “Requirements for Non-keyboard Input Devices,” provides guidance on how to measure the effectiveness and usability of nonkeyboard computer input devices.5908
Table 11.6 Control And Input Devices For Human-Computer Interaction
Device |
Conditions for Appropriate Use |
Cursor Control Keys |
Cursor moves in X and Y dimensions. |
Touch Screen |
Moving/holding arm to screen for long periods of time is not required. Screen does not have small poke points relative to size of fingertip. A low level of resolution is required for positioning. Task will not be disrupted by hand temporarily blocking screen. |
Light Pen |
High positioning precision is not required. Holding arm to screen for long periods of time is not required. |
Mouse |
Adequate space is available for mouse movement over a pad or desktop. A low-to-medium level of resolution is required for positioning. Periodic cleaning is provided. |
Isotonic Joystick (Displacement) |
Positioning accuracy is more important that positioning speed. |
Trackball |
Rapid cursor positioning is desirable. Limited space is available for installing an input device. |
Graphics Tablet |
A low-to-medium level of resolution is required. |
Isometric Joystick (Force) |
Precise or continuous control of two or more related dimensions is required. |