title: Valid characters for directory part of a URL (for short links)
body: <p>Are there any other characters except A-Za-z0-9 that can be used to shorten links without getting into trouble? :)</p>
  
  <p>I was thinking about +,;- or something.</p>
  
  <p>Is there a defined standard regarding what characters can be used in a URL that browser vendors respect?</p>