title: Java Math.random
body: <p>I been searching for the logic of Math.random through book, however I can't get to understand</p>
  
  <pre><code>((char)('A' + Math.random() * 27))
  </code></pre>
  
  <p>What does 27 means? I tried to replace with 100, the results is it generates some special characters like !@#$%^&amp;*((
  I'd appreciate if you could give me more info about this. TQ</p>