Headings

Six levels of heading are supported. (Note that a hypertext node within a hypertext work tends to need fewer levels of heading than a work whose only structure is given by the nesting of headings.)

A heading element implies all the font changes, paragraph breaks before and after, and white space (for example) necessary to render the heading. Further character emphasis or paragraph marks are not required in HTML.

H1 is the highest level of heading, and is recommended for the start of a hypertext node. It is suggested that the the text of the first heading be suitable for a reader who is already browsing in related information, in contrast to the title tag which should identify the node in a wider context.

The heading elements are

		<H1>, <H2>, <H3>, <H4>, <H5>, <H6>

It is not normal practice to jump from one header to a header level more than one below, for example for follow an H1 with an H3. Although this is legal, it is discouraged, as it may produce strange results for example when generating other representations from the HTML.

Example:

		<H1>This is a heading</H1>
		Here is some text
		<H2>Second level heading</H2>
		Here is some more text.

Parser Note:

Parsers should not require any specific order to heading elements, even if the heading level increases by more than one between successive headings.

Typical Rendering

H1

Bold very large font, centered. One or two lines clear space between this and anything following. If printed on paper, start new page.

H2

Bold, large font,, flush left against left margin, no indent. One or two clear lines above and below.

H3

Italic, large font, slightly indented from the left margin. One or two clear lines above and below.

H4

Bold, normal font, indented more than H3. One clear line above and below.

H5

Italic, normal font, indented as H4. One clear line above.

H6

Bold, indented same as normal text, more than H5. One clear line above.

These typical values are just an indication, and it is up to the designer of the presentation software to define the styles. The reader may have options to customize these. When writing documents, you should assume that whatever is done it is designed to have the same sort of effect as the styles above.

The rendering software is responsible for generating suitable vertical white space between elements, so it is NOT normal or required to follow a heading element with a paragraph mark.