ong></td>
    <td>File systems are organised into directories in much the same way that 
      filing cabinets are organised into draws and folders. Your files should 
      be stored in a directory that you have created. This keeps your files from 
      getting muddled up with all the other files on the computer.</td>
  </tr>
  <tr valign="top"> 
    <td><strong>Divide by zero </strong></td>
    <td>This will cause an error. Any number divided by zero is infinitely big. 
      This can not be cal