HTML tables are used to present data in a tabular format. Tables are defined with the <table> element, and table rows are defined with the <tr> element. Table cells are defined with the <td> element (for data cells) or the <th> element (for table headers).

Here is an example of a simple HTML table:

<table>
<tr>
<th>Name</th>
<th>Email</th>
<th>Phone</th>
</tr>
<tr>
<td>Alice</td>
<td>alice@example.com</td>
<td>555-555-1212</td>
</tr>
<tr>
<td>Bob</td>
<td>bob@example.com</td>
<td>555-555-1213</td>
</tr>
</table>

This will create a table with three columns (Name, Email, and Phone) and two rows of data.

You can also use the <thead>, <tbody>, and <tfoot> elements to group rows within the table. The <thead> element is used to define a set of rows that make up the table header, the <tbody> element is used to define the main content of the table, and the <tfoot> element is used to define a set of rows that make up the table footer.

Here is an example of a table using these elements:

<table>
<thead>
<tr>
<th>Name</th>
<th>Email</th>
<th>Phone</th>
</tr>
</thead>
<tbody>
<tr>
<td>Alice</td>
<td>alice@example.com</td>
<td>555-555-1212</td>
</tr>
<tr>
<td>Bob</td>
<td>bob@example.com</td>
<td>555-555-1213</td>
</tr>
</tbody>
<tfoot>
<tr>
<td colspan="3">Total: 2</td>
</tr>
</tfoot>
</table>

This table is similar to the previous example, but it also has a footer row at the bottom that spans all three columns and displays the total number of rows in the table.