html tag

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

# HTML 5 <html> tag

## Definition and Usage

This element tells a browser that this is an HTML document.

## Differences Between HTML 4.01 and HTML 5

HTML 4.01 had an xmlns attribute, which was required in XHTML. This really had no effect in HTML 4.01, but was useful while converting from HTML to XHTML, for validational reasons. In HTML 5 there is no reason to do this, but you can define the xmlns attribute with the value "http://www.w3.org/1999/xhtml".

HTML 5 has a new attribute: manifest

## Tips and Notes

Note: If you, for some reason, wish to define the xmlns attribute, the ONLY legal value is "http://www.w3.org/1999/xhtml"

## Example

<html>

<head>
</head>

<body>
...
...
...
</body>

</html>

## 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
--- | --- | --- | --- | ---
manifest | url | Defining cache information for offline use | 4 | 5
xmlns | http://www.w3.org/1999/xhtml | Defines the XML namespace attribute. Do not use this attribute in HTML 5 | 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.

## Try-It-Yourself Demos

A very simple HTML document
A very simple HTML document, with only a minimum of HTML tags. It demonstrates how the text inside a body element is displayed in the browser.

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