HTML & XHTML: The Definitive Guide, 6th Edition

The <li> Tag

It should be quite obvious to you by now that the <li> tag defines an item in a list. It's the universal tag for list items in ordered (<ol>) and unordered (<ul>) lists, as we discussed earlier, and for directories (<dir>) and menus (<menu>), which we discuss in detail later in this chapter.

Because the end of a list element can always be inferred by the surrounding document structure, most authors omit the ending </li> tags for their HTML list elements. That makes sense because it becomes easier to add, delete, and move elements around within a list. However, XHTML requires the end tag, so it's best to get used to including it in your documents.

Although universal in meaning, there are some differences and restrictions to the use of the <li> tag for each list type. In unordered and ordered lists, nearly anything can follow the <li> tag, including other lists and multiple paragraphs. Typically, if it handles indentation at all, the browser successively indents nested list items, and the content in those items is justified to the innermost indented margin.

<li>

Function	Defines an item within an ordered, unordered, directory, or menu list
Attributes	class, dir, id, lang, onClick, onDblClick, onKeyDown, onKeyPress, onKeyUp, onMouseDown, onMouseMove, onMouseOut, onMouseOver, onMouseUp, style, title, type, value
End tag	</li>; often omitted in HTML
Contains	flow
Used in	list_content

Directory and menu lists are another matter. They are lists of short items, like a single ...