How to use colspan and rowspan in HTML tables?

To use colspan and rowspan in HTML tables, we set the rowspan and colspan attributes.

For instance, we write

<table>
  <tbody>
    <tr>
      <td rowspan="2">LEFT</td>
      <td>1</td>
      <td>2</td>
      <td>3</td>
      <td>4</td>
      <td rowspan="2">RIGHT</td>
    </tr>
    <tr>
      <td>5</td>
      <td>6</td>
      <td>7</td>
      <td>8</td>
    </tr>
    <tr>
      <td>-</td>
      <td>-</td>
      <td>-</td>
      <td>-</td>
      <td>-</td>
      <td>-</td>
    </tr>
  </tbody>
</table>

to set the rowspan attribute to 2 to maker the td span 2 rows.