colgroup tag

Question

wt is the function of <colgroup> and <col>?can anyone give me a clear example?

Answer 1

The HTML <colgroup>element defines a group of columns within a table. If the span attribute is present: none, it is an empty element. The start tag may be omitted, if it has a <col> element as its first child and if it is not preceded by a <colgroup> whose end tag has been omitted.

<table>
  <colgroup>
    <col span="2"style="background-color:red">
    <col style="background-color:yellow">
  </colgroup>
  <tr>
    <th>ISBN</th>
    <th>Title</th>
    <th>Price</th>
  </tr>
  <tr>
    <td>3476896</td>
    <td>My first HTML</td>
    <td>$53</td>
  </tr>
</table>