title: How do I find the 'namespace keyword' of an included file?
body: <p>I'm a novice C++ programmer.
  How can I find out the namespace (is this the right word in this context?) for an include like <em>'iomanip'</em> or any other?
  When using <em>'std::cout'</em>, I don't know why it's <em>'std'</em> and not something else.</p>
  
  <p>I hope my question is clear and worth asking.</p>
  
  <p>PS: My first post here :)</p>