Definition: There are six levels of headings defined in HTML. All paragraph breaks before and after, font changes, and any white space necessary to render the heading are implied by the heading element. The heading elements are H1, H2, H3, H4, H5, and H6. H1 is the highest (or most important) level and H6 is the least.
Standard Attributes: CLASS, CLEAR, ID, LANG
Horizontal headings are normally rendered flush left. You can use the ALIGN attribute to specify an explicit horizontal alignment:
* align=right: Renders the heading flush right
* align=left: Renders the heading flush left
* align=center: Centers the heading
* align=justify: Allows heading lines to be justified where it's practical @md where it's not, it gives the same effect as the default setting.
SEQNUM stands for a sequence number that is associated with each level of header from H1 (the top level) to H6 (the bottom level). You can use this attribute to set the sequence number that's associated with the current element's header level to a given number, such as SEQNUM=9. It's typical to have the sequence number initialized to 1 at the document's beginning and incremented after each header element. Any header element of a higher level also resets it to 1. The style sheet is responsible for controlling this style of header numbering.
SKIP is used if headers have been omitted from the sequence. It will increment the sequence number before rendering the element. SKIP=5 would advance the sequence number past 5 omitted items.
DINGBAT specifies an iconic image that will appear before the header. The icon must be specified as an entity name @md an appendix of this specification lists standard entity names for HTML 3.0.
SRC specifies the graphical content of a figure, while the image is specified as a URI. You may see this attribute together with the MD attribute.
MD specifies a cryptographic checksum or message digest for the associated graphic (specified by the SRC attribute). Use it when you want to make sure that a linked object is the same one that was intended by the document's author, and that the object hasn't been modified at all. Elements which support URI-based links generally allow the MD attribute.
You can prevent the browser from automatically wrapping lines by using NOWRAP. If you would like to specify explicit line breaks, you can then do it by using the BR element.
Context: <H*> is legal within
<A>, <BANNER>, <BODY>, <BODYTEXT>, <DIV>, <FIGTEXT>, <FN>, <FORM>, <NOTE>, <TD>, <TH>
The following markup can be used within <H*>
<A>, <ABBREV>, <ACRONYM>, <AU>, <B>, <BIG>, <BR>, <CITE>, <CODE>, <DEL>, <DFN>, <EM>, <I>, <IMG>, <INS>, <KBD>, <LANG>, <MATH>, <PERSON>, <Q>, <S>, <SAMP>, <SMALL>, <STRONG>, <SUB>, <SUP>, <TAB>, <TT>, <U>, <VAR>
Suggested style/usage: Close Tag: REQUIRED
Examples: <H2>A Good Beginning</H2>