title: What is arbitrary data/JSON?
body: <p>I've recently come across the term arbitrary data/ arbitrary json and i can't seem to understand what exactly is it and/or find any documentation on it. I know that JSON is a format for sending data over the internet, so how exactly can a format be arbitrary?</p>
  
  <p>EDIT::</p>
  
  <p>//more code</p>
  
  <pre><code>  var buildItem = function(item) {
      var title = item.name,
          args = [],
          output = '&lt;li&gt;';
  
      if (item.type == 'method' || !item.type) {
        if (item.signatures[0].params) {
          $.each(item.signatures[0].params, function(index, val) {
            args.push(val.name);
          });
        }
        title = (/^jQuery|deferred/).test(title) ? title : '.' + title;
        title += '(' + args.join(', ') + ')';
      } else if (item.type == 'selector') {
        title += ' selector';
      }
      output += '&lt;h3&gt;&lt;a href="' + item.url + '"&gt;' + title + '&lt;/a&gt;&lt;/h3&gt;';
      output += '&lt;div&gt;' + item.desc + '&lt;/div&gt;';
      output += '&lt;/li&gt;';
  
      return output;
    };
  
  //more code
  </code></pre>
  
  <p>in the example code above, i am told that the .params is <strong>arbitrary data</strong> from a JSON request [for the jQuery API documentation]. </p>
  
  <p>What then is arbitrary data?</p>
  
  <p>Would really appreciate any answers and/or clarifications.</p>
  
  <p>jsFiddle: <a href="http://jsfiddle.net/QPR4Z/2/" rel="noreferrer">http://jsfiddle.net/QPR4Z/2/</a></p>
  
  <p>Thanks!</p>