title: What is 'Push Approach' and 'Pull Approach' to parsing?
body: <blockquote>
    <p>Under the push parsing approach, a push parser generates synchronous events as a document is
    parsed, and these events can be processed by an application using a callback handler model  </p>
  </blockquote>
  
  <p>This is the text given in the book <em>Pro XML Development with Java</em> about SAX 2.0. </p>
  
  <p>As for StAX, the book says:  </p>
  
  <blockquote>
    <p>Under the pull approach, events are pulled from an XML document under the control of the application
    using the parser. </p>
  </blockquote>
  
  <p>I want to ask, what is the meaning of the highlighted text ?  An answer befitting a beginner is appreciated :)</p>