Header scope
<html> <body> <table id="myTable"> <tr> <th id="myTableHeader">Row 1</th> <td>Cell</td> <td>Cell</td> <td>Cell</td> <td id="td1">Cell info 1</td> <td>Cell</td> </tr> </table> <script language="JavaScript"> document.all.myTableHeader.scope = "colgroup"; </script> <button onclick="alert('This cell provides header information for its col.');"> Cell info 1 </button> </body> </html>