The purpose of the Ergonomics section is to provide ground rules for healthy and proper work with the various computer elements: how to hold the mouse? how to use the keyboard? etc.
Diagrams and illustrations are featured in the Ergonomics presentation to demonstrate "do and don't"s.

Lay your hand gently over the mouse. Do not grip it tightly.
Your pointing finger and your ring finger should be on the buttons, with your middle finger on the scroll wheel in the center.
If you are left-handed, here is how you would hold the mouse.
Keep your wrist straight. Do not turn your hand to the left or to the right.
Keep your wrist straight. Do not raise or lower your arm
Keep your wrist straight when you place your hands on the keyboard.
Do not turn your hands outward.
Do not turn your hands inward.
Just like using the mouse, keep your arm and wrist straight. Do not bend your arm up or down.
Be sure to sit properly at your computer.
Head should be kept straight and not tilted back or forward to see the screen.
Adjust the chair, armrests, and table height so you
Adjust the chair, armrests, and table height so your hands, arms, and wrists are straight.
Sit straight and place your feet on a footstool if needed to keep your thighs parallel to the floor.
Take breaks often!
Focus your eyes on something else across the room. Stretch your shoulders, neck, and arms.
Stop now and take a look at your posture, your arms, and your hands. Is everything as it should be?