There are two issues at stake when it comes to evaluating the potential health risks of using computers. The first has to do with radiation; the second is eye strain.
Most modern home computers emit a negligible amount of radiation. If the radiation from the average computer were really harmful to babies, then it would be harmful to everyone, and we would ALL be told to stay away from the computer!
However, the old CRT (cathode ray tube) monitors – the big, bulky kind – do emit a significant amount of potentially harmful radiation. People who are particularly sensitive (estimated to be around 20% of the population) can suffer ill effects from prolonged exposure, with symptoms including lowered immunity and moodiness. Thankfully, LCD monitors – which do not have this problem – have become the norm in most countries.
If you are using a CRT monitor with your computer, it is advisable to get an LCD monitor as soon as possible. CRT TVs remain relatively common around the world – and if you are using one, then it is important not to sit too close and a good idea to limit screen time, too.
As for eye strain, this largely depends on the type of monitor – and in particular, its refresh rate. CRT monitors have very low refresh rates – if you look closely at one of these old monitors, you will see the screen flickering. Over time, this tends to cause eye strain. Again, thankfully, modern monitors have very high refresh rates and this problem has been reduced considerably. Many people who used to have eye-strain problems with CRT screens do not have problems with LCD or plasma screens.
One final note has to do with glare – make sure the lighting is adequate!