HTML 5 optgroup tag

From http://www.w3schools.com (Copyright Refsnes Data)

# HTML 5 <optgroup> tag

## Definition and Usage

Defines an option group. This element allows you to group choices. When you have a long list of options, groups of related choices are easier to handle.

## Differences Between HTML 4.01 and HTML 5

NONE

## Example

Source | Output
--- | ---

<select>
<optgroup label="Swedish Cars">
<option value ="volvo">Volvo</option>
<option value ="saab">Saab</option>
</optgroup>
<optgroup label="German Cars">
<option value ="mercedes">Mercedes</option>
<option value ="audi">Audi</option>
</optgroup>
</select>

## Attributes

- 4: indicates if the attribute is defined in HTML 4.01
- 5: indicates if the attribute is defined in HTML 5

Attribute | Value | Description | 4 | 5
--- | --- | --- | --- | ---
label | text_label | Defines the label for the option group | 4 | 5
disabled | disabled | Disables the option-group when it first loads | 4 | 5

## Standard Attributes

class, contenteditable, contextmenu, dir, draggable, id, irrelevant, lang, ref, registrationmark, tabindex, template, title

For a full description, go to Standard Attributes in HTML 5.

## Event Attributes

onabort, onbeforeunload, onblur, onchange, onclick, oncontextmenu, ondblclick, ondrag, ondragend, ondragenter, ondragleave, ondragover, ondragstart, ondrop, onerror, onfocus, onkeydown, onkeypress, onkeyup, onload, onmessage, onmousedown, onmousemove, onmouseover, onmouseout, onmouseup, onmousewheel, onresize, onscroll, onselect, onsubmit, onunload

For a full description, go to Event Attributes in HTML 5.

From http://www.w3schools.com (Copyright Refsnes Data)