As mentioned,
there are two obligatory constructs in
HTML 3.2
and they must appear in this order:
Most browsers don't complain if you omit these,
but they are required by the
HTML 3.2 definition. More importantly,
there are good practical reasons to include them:
-
The !DOCTYPE clause, which is a reference to a document type
definition (DTD) in the SGML metalanguage,
is very relevant when the document is
processed by a general SGML browser (instead of a much more specialized
program, an HTML browser, such as a typical WWW browser).
Moreover, specifying the
version
of HTML used in the document
is useful to people who study your HTML code, and it might
be relevant to WWW browsers and editors, too.
- The document name in the TITLE
element is used for several useful purposes by browsers and other software.
Typically, it is displayed in hotlists, results returned by
search engines,
etc.
Formally,
the TITLE element is (at least implicitly) part of a
HEAD element
whereas the !DOCTYPE clause precedes all HTML constructs.
Optionally, the HEAD element
may contain
the following elements in addition to a TITLE element:
- an ISINDEX element (not used much any more)
- a BASE element, specifying the implicit base
address of URL references
- META elements providing various
metainformation, for example document expiration date
- LINK elements, which also provide metainformation
but about the relationships of the document with other documents
- STYLE and
SCRIPT elements; they are expected to be very
important in the future but they are not usable yet (since both
standardization and implementation is in progress).
Date of last update:
2010-12-16.