Concept

The <fieldset> tag in HTML is used to group elements together in a form. It creates a frame around the group elements to form a logical group.

Usage

<form>
  <fieldset>
    <legend>Thông tin cá nhân</legend>
    <label for="name">Họ tên:</label>
    <input type="text" id="name" name="name"><br><br>
    <label for="email">Email:</label>
    <input type="email" id="email" name="email"><br><br>
    <label for="password">Mật khẩu:</label>
    <input type="password" id="password" name="password"><br><br>
  </fieldset>
</form>

Result

In the above example, <fieldset> is used to group elements related to personal information in a form. <legend> is used to define a title for the group.