Using a Computer can cause Health problems

The Telegraph reported in 2009 that teenagers spend, on average, 31 hours online a week. The effects of such extensive computer usage have been long debated, and studies have shown various long-term and short-term health problems attributable to excessive computer usage.
Repetitive Strain Injury

Repetitive strain injury occurs when areas of the body have been subjected to repetitive movements over a long period of time. Typing, mouse usage and even poor posture can cause repetitive strain injury. Symptoms can range from mild pain to severe pain and inflammation. The effects are usually temporary and decrease with rest.
Eye Strain

Eye strain happens when you strain your eyes by using them continuously, causing pain and headaches. This can happen because of reading, studying and computer usage, especially if you don't take enough breaks while using your computer for several hours. Usually eye strain is only temporary and will go away once you rest your eyes.
Back/Shoulder Pain

Poor posture and continual computer usage can result in back and shoulder pain, according to a study of 30,000 teenagers from the University of Bergen, Norway, reported in June 2010. While computer overuse is unlikely to cause permanent damage, it can become a problem when it results in continuous pain. Correcting your posture and taking plenty of breaks can alleviate some of the symptoms.
Depression

Using the computer to search for health complaints can result in depression, according to a 2010 study by Carnegie Mellon University. Using the computer once a day for health purposes increased symptoms of depression, but using the computer to communicate with friends and family decreased symptoms of depression. Moderate computer usage may actually be beneficial to your mental health if you are using the computer for social reasons as well.