title: javascript doesn't set the value of td tag
body: <p>I'm very new to JavaScript and I wish I could set the value of a <code>td</code> tag using JavaScript.</p>
  
  <p>I have code like this to do so:</p>
  
  <pre><code>window.onload = function() {
       document.getElementById("units").value = "122"
  }
  </code></pre>
  
  <p>And I have a html file like this:</p>
  
  <pre><code>&lt;table class="table" width="100%"&gt;
      &lt;caption class="bold"&gt;TNEB UnitCalculator&lt;/caption&gt;
      &lt;tbody&gt;
          &lt;tr&gt;
              &lt;td&gt;testing&lt;/td&gt;
              &lt;td id="units"&gt;&lt;/td&gt;
          &lt;/tr&gt;
      &lt;/tbody&gt;
  &lt;/table&gt;
  </code></pre>
  
  <p>But that doesn't seems to be working!</p>