title: Why and how should I use namespaces in C++?
body: <p>I have never used namespaces for my code before. (Other than for using STL functions)</p>
  
  <ol>
  <li>Other than for avoiding name conflicts, is there any other reason to use namespaces?</li>
  <li>Do I have to enclose both declarations and definitions in namespace scope?</li>
  </ol>