title: Use and meaning of "in" in an if statement?
body: <p>In an example from Zed Shaw's <em>Learn Python the Hard Way</em>, one of the exercises displays the following code:</p>
  
  <pre><code>next = raw_input("&gt; ")
  if "0" in next or "1" in next:
      how_much = int(next)
  </code></pre>
  
  <p>I'm having a hard time understanding the meaning of <code>in</code> in this statement. I'm used to using <code>if</code> statements, such as in javascript, where the syntax is something like:</p>
  
  <pre><code>var = 5;
  if (var &gt; 3) {
      //code  to be executed
  }
  </code></pre>
  
  <p>Is this <code>if</code> / <code>in</code> statement (in python) the same as <code>if()</code> in javascript?</p>
  
  <p>Finding an answer to this has been tricky because the <code>in</code> is such a short string to narrow down an answer via search engine, and I don't know the proper name for its operation.</p>