title: Is TimeZone.setTimeZone("est") different from TimeZone.setTimeZone("EST")
body: <p>When I write this code:  </p>
  
  <pre><code>   Calendar cal = Calendar.getInstance();
     cal.setTimeZone(TimeZone.getTimeZone("EST"));
     System.out.println(cal.getTimeZone().getDisplayName());
  </code></pre>
  
  <p>The output is</p>
  
  <pre><code>   Eastern Standard Time
  </code></pre>
  
  <p>But when I write this code:</p>
  
  <pre><code>   Calendar cal = Calendar.getInstance();
     cal.setTimeZone(TimeZone.getTimeZone("est"));
     System.out.println(cal.getTimeZone().getDisplayName());
  </code></pre>
  
  <p>The output I get is:</p>
  
  <pre><code>   GMT-05:00
  </code></pre>
  
  <p>Is there any difference in giving arguments like "EST" and "est" when setting <code>TimeZone.setTimeZone(String str)</code>     (Is <code>str</code> to be passed when calling considered CASE SENSITIVE)?</p>
  
  <p>The API doesn't mention anything about it: </p>
  
  <pre><code>getTimeZone
  
  public static TimeZone getTimeZone(String ID)
  
  Gets the TimeZone for the given ID.
  
  Parameters:  
  ID - the ID for a TimeZone, either an abbreviation such as "PST", a full name such as "America/Los_Angeles", or a custom ID such as "GMT-8:00".   
  Note that the support of abbreviations is for JDK 1.1.x compatibility only and full names should be used.
  
  Returns:
  the specified TimeZone, or the GMT zone if the given ID cannot be understood.
  </code></pre>
  
  <p>NOTE: I tried with <code>IST</code> and <code>ist</code> strings. For <code>IST</code> string it gives <code>Indian Standard Time</code> and for <code>ist</code> it gives <code>Greenwich Mean Time</code></p>