Em html

Definition and Usage

The tag defines a division or a section in an HTML document.

The tag is used to group block-elements to format them with styles.
Tips and Notes

Tip: The element is very often used together with CSS, to layout a web page.

Note: By default, browsers always place a line break before and after the element. However, this can be changed with CSS.
Differences Between HTML and XHTML

NONE
Optional Attributes

DTD indicates in which HTML 4.01/XHTML 1.0 DTD the attribute is allowed. S=Strict, T=Transitional, and F=Frameset.
Attribute Value Description DTD align left right center justify Deprecated. Use styles instead.
Specifies the alignment of the content inside a element TF

Standard Attributes

The tag supports the following standard attributes:
Attribute Value Description DTD class classname Specifies a classname for an element STF dir rtl ltr Specifies the text direction for the content in an element STF id id Specifies a unique id for an element STF lang language_code Specifies a language code for the content in an element STF style style_definition Specifies an inline style for an element STF title text Specifies extra information about an element STF xml:lang language_code Specifies a language code for the content in an element, in XHTML documents STF

More information about Standard Attributes.
Event Attributes

The tag supports the following event attributes:
Attribute Value Description DTD onclick script Script to be run on a mouse click STF ondblclick script Script to be run on a mouse double-click STF onmousedown script Script to be run when mouse button is pressed STF onmousemove script Script to be run when mouse pointer moves STF onmouseout script Script to be run when mouse pointer moves out of an element STF onmouseover script Script to be run when mouse pointer moves over an element STF onmouseup script Script to be run when