title: What is action ID in Photoshop script?
body: <p>I read a tutorial of photoshop scripting,
  and I can't understand this line.</p>
  
  <pre><code>//get action ID
  cTID = function(s) { return app.charIDToTypeID(s); }; 
  sTID = function(s) { return app.stringIDToTypeID(s); }; 
  </code></pre>
  
  <p>I think these codes are call Photoshop actions, 
  but I don't have any references, so 
  I can't really understand how to use these.
  Why are they need and How to use these?</p>