Sitting at Your Computer
When you use the computer, try to keep your elbows, hips, and knees bent at approximately 90 degree angles and keep your wrists as close to horizontal as possible. (Your hands, forearms, and thighs should be horizontal and your upper arms and lower legs should be vertical.) Your feet should rest firmly on the floor or a footrest.
An adjustable chair allows you to customize your workstation for your body so you can maintain the right posture. To avoid back problems, make sure your chair supports your lower back. Padded armrests let you rest your arms as you work.
To reduce neck strain, keep source documents on a copy stand and position the stand next to the screen at the same eye level.