1.label

<form>
<label for="yourName">Your Name</label>

    <input name="yourName" id="yourName">

    <!-- etc. -->
</form>

id for the  to associate it to.

2.fieldset & legend

<form action="somescript.php" >
<fieldset>
<legend>Name</legend>

        <p>First name <input name="firstName"></p>

        <p>Last name <input name="lastName"></p>
</fieldset>
<fieldset>
<legend>Address</legend>

        <p>Address <textarea name="address"></textarea></p>

        <p>Postal code <input name="postcode"></p>
</fieldset>

    <!-- etc. -->

3.optgroup label

<select name="country">
<optgroup label="Africa">

        <option value="gam">Gambia</option>

        <option value="mad">Madagascar</option>

        <option value="nam">Namibia</option>
</optgroup>
<optgroup label="Europe">

        <option value="fra">France</option>

        <option value="rus">Russia</option>

        <option value="uk">UK</option>
</optgroup>
<optgroup label="North America">

        <option value="can">Canada</option>

        <option value="mex">Mexico</option>

        <option value="usa">USA</option>
</optgroup>

</select>

4.<input name="firstName" accesskey="f" tabindex="1">