Level 0 /
Level 1 /
Level 2 /
Level 3 /
Netscape Mozilla /
Microsoft Internet Explorer
Level 0 HTML Summary
An HTML document consists of text and tags that mark the structure
of the document. Elements in an HTML document are delimited by
the tags which include < and >.
Some elements have both a start and
end tag: e.g., <TITLE> and </TITLE>. Other elements
use only a single tag: e.g., <P> (the paragraph element).
Some elements have attributes, which are
qualifications of the element's meaning or optional parameters
for that element.
A Level 0 HTML document can include the following elements
with the attributes shown. In this document,
the elements are listed in all capital
letters (e.g., TITLE), and the attributes are indicated by initial
capital letters (e.g., Href). In order to benefit from the information
in this document, view both its HTML source
as well as its rendered form
in a Web browser. The elements and entities are explained in the list
below as well as demonstrated here in appropriate locations
(e.g, HEAD elements are demonstrated only in the HEAD of this document;
and I don't demonstrate the heading (H1...H6) within the list of elements).
Note that the different brands of browsers vary in how they render
these features. The intent of HTML is that the browser designers have
specified at each level of HTML
a "basic set" of features that they should implement, so that their browser
renders these HTML constructs some satisfactory way.
The HTML element identifies the file as
containing HTML elements. Only
HEAD, BODY, and comment elements that should go inside the
HTML element start and stop tag.
Comments can be included anywhere within
an HTML document; comments can cross several lines of text:
<!-- this is a comment -->
- Document Type Declaration:
A document type declaration can be placed at the start of a
an HTML document (before the opening <HTML> tag
which identifies it as a document conforming to
a particular version and level of HTML.
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML Level 0//EN">
identifies this document as conforming to the specification
of Level 0 HTML.
The HEAD and Related Elements
The HEAD element brackets a set of unordered descriptive
information about a document. Elements within the HEAD
element include: TITLE, BASE, ISINDEX, and NEXTID.
Every HTML must have one title element which
identifies the contents of the document.
The title may not contain anchors, paragraph elements, or
highlighting. Choose a title which is descriptive
outside the context of the document's creation, as
the title is commonly used to identify a document
in navigation and indexing applications (e.g., hotlists
The BASE element can be used to record the
URL of the original version of a document when
the source file is transported elsewhere; the base element
has one attribute, Href, which is used to
define the base URL of the document. Partial
URLs in the document are resolved by using this
base address as the start of the URL.
This element marks the document as searchable--the
server on which the document is located must have a
search engine defined that supports this searching.
- LINK: this element is used to define a relationship between the
document and other objects or documents.
For example, a link element can indicate
authorship or indicate the tree structure of a document.
The LINK element has the same attributes as the Anchor (A) element:
- Href: this identifies the document or part of
a document to which this link refers
- Name: this is a way to name this LINK as a possible
destination for another hypertext document
- Rel: describes the relationship defined by
according to the possible relationships as defined by the
HTML Registration Authority's list of
For example, the value "made" for Rel indicates that
(in which the Rev="made" statement is placed)
is the creator
of the document referenced in the Href
- Rev: Similar to Rel, above, but the
indicates the reverse relationship as Rel. For
Example, the LINK with Rev="made" indicates that the
Href refers to who "made" the current document.
This is commonly done to indicate authorship of
- Urn: This indicates the Uniform Resource Name of
the document; the specification for
and other addressing is still in development.
- Title: This attribute is not to be used
as a substitute for the TITLE attribute of the document itself,
but as a title for the document given by the Href attribute
of the LINK element. This attribute is rarely used or supported by
browsers, but may have value for cross referencing the
relationships the LINK element defines.
- Methods: This attribute describes the HTTP methods the
object referred to by the Href of the LINK element
supports. For example, one method is searching; a browser
could thus use this Methods attribute to give information to
the user about the document defined by the LINK element.
This element is used to identify meta-information (information about
information) in the document. This element is not meant to take the
place of elements which already have a purpose, for example the
TITLE element, but to identify other information useful for parsing.
Attributes (see the header of this document for typical examples):
This element is used by text generated software
in creating identifiers; its attribute, N, is
used to define the next identifier to be
allocated by the text generator program. Normally,
human writers of HTML don't use this element; and
Web browsers ignore this element.
The BODY and Related Elements
Copyright © 1995-1996 by John December. All rights reserved.
03 Jun 1996