Mathematics [math.stackexchange.com] is indeed the site for "normal" people. The welcome text says:
This is a collaboratively edited question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.
I'd say that would be the appropriate site to post your question (unless it contains source code and/or is about a specific programming language, then you might consider posting it on Stack Overflow, instead).
You're correct about Math Overflow being exclusively for professional mathematicians. A question that is deemed "too basic" is very likely to be closed there. It is not operated by the Stack Exchange 2.0 network (the group that runs this site and Mathematics, among others). Their FAQ says:
MathOverflow's primary goal is for users to ask and answer research level math questions, the sorts of questions you come across when you're writing or reading articles or graduate level books. Of course, individual questions don't have to be worthy of an article, and they don't have to be about new mathematics. A typical example is, "Can this hypothesis in that theorem be relaxed in this way?"