Stealing Shog's comment-as-answer.
If the community has a consensus on anything, it's that simple questions are OK if:
The answers can be interesting.
It looks like there's a real problem being solved.
The person asking has shown an honest effort and at least a modicum of understanding.
Folks going through a book asking for dictionary definitions or stuff that they could have trivially found in literally the #1 search result for anything remotely close to what they are asking are going to get some pushback.
Related:
http://blog.stackoverflow.com/2011/02/are-some-questions-too-simple/https://blog.stackoverflow.com/2011/02/are-some-questions-too-simple/
And of course duplicates should always be closed as duplicates, but this vastly understates the amount of effort it takes to find and close the duplicates. It's a hell of a lot easier and more scalable if we enforce the idea that the asker has to HELP US, that is, put some work into your question and share the results of your research in your question. Because you did research before asking.. right.. right?