What does this code mean? $.getJSON
<p>i know this:</p>

<pre><code>$.getJSON(
  "test.js",
  function(json){
    alert("JSON Data:   " + json.users[3].name);
  }
); 
</code></pre>

<p>but i see the code in a site:</p>

<pre><code>$.getJSON(l, {
                                tag: "userName",
                                userName: 'sss'
                            }
</code></pre>

<p>what is '1' mean,in this place.</p>

<p>thanks</p>
