HP 900 Reference Manual page 43

Operating the OmniBook
Working in Comfort
As with the keyboard, try to keep your hand, wrist, and forearm in a neutral position
while using your mouse or other input device.
When using a stylus or light pen with a graphics tablet, don't grip the stylus tightly.
Keep your hand and fingers relaxed and try to maintain a neutral posture in your
hand, wrist and forearm.
If you use your thumb to rotate the ball on a trackball or spaceball, keep it in a
relaxed, natural shape, and maintain a neutral posture in your hand, wrist, and
forearm.
Hold the mouse gently by draping your fingers over it. Keep your hand relaxed and
fingers loose. Do not grip the mouse tightly.
It takes very little pressure or force from your fingers to activate the buttons or scroll
wheel on your mouse, scrolling mouse, trackball, or other input device. Using too
much force can place unnecessary stress on the tendons and muscles in your hands,
wrists, and forearms.
If you are using a scrolling mouse, be sure to keep your fingers and hand in a relaxed,
neutral position when activating the scroll wheel. Also, this type of mouse features
software that can minimize the number of mouse movements or button clicks.
When using a mouse, trackball, stylus and graphics tablet, or other input device,
position it as close to the keyboard as possible, and keep it at the same level so you do
not have to stretch while using it.
Use a good quality mouse pad to enable the mouse to work most effectively and
reduce unnecessary hand and wrist movements.
Be sure to keep your mouse and trackball clean. Regular removal of accumulated dust
and dirt helps ensure proper tracking and reduces unnecessary hand and wrist
motions.
Reference Guide 43