HTML / XHTML Standard Attributes

The attributes listed below are standard, and are supported by all HTML and XHTML tags, with a few exceptions.

Core Attributes

Not valid in base, head, html, meta, param, script, style, and title elements.

Attribute	Value	Description
class	classname	Specifies a classname for an element
id	id	Specifies a unique id for an element
style	style_definition	Specifies an inline style for an element
title	text	Specifies extra information about an element

Not valid in base, br, frame, frameset, hr, iframe, param, and script elements.

Attribute	Value	Description
dir	ltr rtl	Specifies the text direction for the content in an element
lang	language_code	Specifies a language code for the content in an element. Language code reference
xml:lang	language_code	Specifies a language code for the content in an element, in XHTML documents. Language code reference

Attribute	Value	Description
accesskey	character	Specifies a keyboard shortcut to access an element
tabindex	number	Specifies the tab order of an element