title: Does C# need the private keyword?
body: <p>(inspired by <a href="https://stackoverflow.com/questions/6348924/enum-inheriting-from-int#comment7429503_6348924">this comment</a>)</p>
  
  <p>Is there ever a situation in which you <em>need</em> to use the <code>private</code> keyword?<br>
  (In other words, a situation in which omitting the keyword would result in different behavior)</p>