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There are several types of head pointers. One of the original types consists of a helmet to which is attached a long rod. Keys are hit on a keyboard with this rod, but this may not be a comfortable method of data entry and can transfer stress to the neck.

Newer head pointers are electronic and move the cursor in response to head movements. They require the person to wear an infrared (Headmaster) or micro-gyroscope (Tracer) sensor on his head or perhaps a reflective dot (Tracker, HeadMouse). The system measures signals from the sensors, or looks at the way light reflects off the dot, to determine whether the user is moving his head up or down, right or left. The cursor is moved in the same direction as the user's head movements. The result is a cursor control method that is completely hands free. Mouse clicks can be performed by activating a separate switch or by holding the mouse position for a certain length of time (dwell mode). However, the user needs to have good head control, some setup assistance may be needed to put on the reflective dot or sensor, and these systems can be expensive (about $1000).

If you don’t want to wear a sensor or marker, one option is the CameraMouse. It uses a camera to capture images of the user's head or face and tracks head movements by measuring changes in that image. It can also track finger or toe movement.

Head pointers are often used in conjunction with virtual, on-screen keyboards.

See the Mouse alternatives article for more cursor control options.