<table border=0 width=100>
<tr><td id=a1>aaaaaaaaaaa</td></tr>
<tr><td id=b1>bbbbbbbbbbb</td></tr>
</table>
<script>
function setcolor()
{
a1.style.background="#ff0000";
b1.style.background="#0000ff";
}
</script>
<input type=button value="set color" onclick="setcolor()">
<tr><td id=a1>aaaaaaaaaaa</td></tr>
<tr><td id=b1>bbbbbbbbbbb</td></tr>
</table>
<script>
function setcolor()
{
a1.style.background="#ff0000";
b1.style.background="#0000ff";
}
</script>
<input type=button value="set color" onclick="setcolor()">
td.tdClass{background-color:#00ffff;}
</style><table border=1>
<tr><td id="td1">abc</td><td>lmn</td></tr>
<tr><td onclick="this.style.backgroundColor='#ff0000'">click here</td><td>xyz</td>
</tr></table>
<input type=button onclick="document.all('td1').style.backgroundColor='#ffff00'" value="User ID"><br>
<input type=button onclick="document.all.tags('table')[0].rows[0].cells[1].style.backgroundColor='#0000ff'" value="User Index"><br>
<input type=button onclick="document.all.tags('table')[0].rows[1].cells[1].className='tdClass'" value="User Class"><br>
<tr>
<td onmouseover="this.bgColor='red'" onmouseout="this.bgColor='green'">1233<br>456</td>
</tr>
</table>