Welcome to the forum! 
In most cases — not all, but most — the problems are the result of the improper behavior of the biological unit between the keyboard and the chair.
Rather than getting into the specifics by repeating myself all over again — as I have already had to do quite a lot on this forum — I will post a little essay I have written a while ago, albeit that not too many newcomers have bothered to read it yet. But it does detail some of the things you can (and should) do to minimize your chances of running into any catastrophes. 