Constant use of a computer or video display terminal can cause eyestrain and fatigue, but they are not harmful to your eyes.
You can use your eyes as much as you wish because they will not wear out. Your vision may change as a function of age or eye diseases, but you cannot wear your eyes out by simply using them.
See your doctor at the very first sign of vision loss or impairment such as blurred vision or flashes of light. If detected early enough and depending on the cause, there are treatments available that may correct, stop, or slow down the loss of vision.
There is no evidence that being right in front of the television will harm your eyes. In fact, children, in particular, may have an easier time focusing up close without eyestrain better than adults. On the other hand, sitting close to the television may be a sign of nearsightedness so check with your doctor if there are other signs or symptoms.
Reading in the dark or dim light can certainly make your eyes tired or may even give you a headache but it will not harm your eyes.
No, children do not truly outgrow crossed eyes. This condition, a misalignment of the eyes called strabismus can develop poor vision. The sooner crossed or misaligned eyes are treated, the less likely it is for the child to have permanently impaired vision.
Contrary to this old adage, your eyes will not stay crossed if you cross them.
There is not enough evidence to support this claim. To the contrary, nightlights in an infant room may help them learn to focus and help with eye coordination skills.