Sony PCG-705 - Manual (Page 138)

Ergonomic Considerations
You will be using your notebook computer as a portable device in a
variety of environments. Whenever possible, you should attempt to
apply the following ergonomic considerations to both stationery and
portable environments.
Position of your computer - The computer should be directly in
front of you as you work. Keep your forearms horizontal with your
wrists in a neutral, comfortable position while using the keyboard,
touchpad, or external mouse. Let your upper arms hang naturally at
your sides. Take breaks during sessions with your computer.
Excessive use of the computer may strain muscles or tendons.
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