title: Confusing byte array
body: <p>I have seen a proper byte array initialization as say</p>
  
  <pre><code>byte[] a = new byte[8];
  </code></pre>
  
  <p>But what does this mean?</p>
  
  <pre><code>byte[] bitfield = new byte [0xFFFFFFF/8];
  n = 18;  // some integer
  bitfield [n / 8] |= 1 &lt;&lt; (n % 8);
  </code></pre>
  
  <p>Please also explain what does <code>0xFFFFFFF/8</code> means here.</p>