title: Java - what does annotation referencing itself do?
body: <p>I stumbled across into the source code for the "Documented" Java Annotation recently.  It looks like this:</p>
  
  <pre><code>@Documented
  @Retention(RetentionPolicy.RUNTIME)
  @Target(ElementType.ANNOTATION_TYPE)
  public @interface Documented {
  }
  </code></pre>
  
  <p>What the purpose of "@Documented" within Documented itself?</p>