HTML colgroup Tag

The <colgroup> tag in HTML is used to group and define properties for a set of columns in an HTML table. It provides a way to apply common styles or attributes to multiple columns simultaneously.

Here’s an example of how the <colgroup> tag is used:

<table>
    <colgroup>
        <col style="background-color: yellow;">
        <col>
        <col style="background-color: lightblue;">
    </colgroup>
    <tr>
        <th>Column 1</th>
        <th>Column 2</th>
        <th>Column 3</th>
    </tr>
    <tr>
        <td>Data 1</td>
        <td>Data 2</td>
        <td>Data 3</td>
    </tr>
</table>

In the example above, the <colgroup> element is used to group the <col> elements together. Each <col> element represents a column in the table. The <colgroup> element is placed before the <tr> elements that define the table rows.

In this example, we have defined three columns using <col> elements within the <colgroup> element. The first <col> element has an inline style applied to it, setting the background color of the column to yellow. The second <col> element doesn’t have any specific styles applied to it. The third <col> element has an inline style applied to it, setting the background color of the column to light blue.

By using the <colgroup> and <col> tags, you can define common properties or styles for a group of columns in a table. This helps apply consistent styling or attributes to multiple columns, reducing repetitive code.

It’s important to note that the <colgroup> and <col> tags do not render any content on their own. They are used to define properties or attributes for columns within the table structure.

Additionally, CSS can be used to style specific columns or apply visual effects to columns in a table. CSS properties like background-color, width, border, and others can be used to customize the appearance of individual columns or groups of columns.

Overall, the <colgroup> and <col> tags provide a way to group and define properties for columns in an HTML table, allowing for more control over the styling and presentation of the table’s structure.