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HTML
Chapter 1
What is HTML?
CONTENTS
HTML at a Crossroads
HTML is not a Programming Language
A Short HTML History
Marking Up Text
Who Decides What HTML Is?
The HTML Working Group
The World Wide Web Consortium
Individual Companies and HTML
Additional Information on HTML Standards and Organizations
Summary
Review Questions
The explosive growth of the World Wide Web is relatively unprecedented,
although it resembles the desktop publishing revolution of the
early and mid-1980s. As personal computers became more common
in homes and offices, people began to learn to use them for document
creation and page layout. Although early word processing programs
were not terribly intuitive and often required memorizing bizarre
codes, people still picked them up fairly easily and managed to
create their own in-house publications.
Suddenly, the same kind of growth is being seen as folks rush
to create and publish pages of a different sort. To do this, they
need to learn to use something called the Hypertext Mark-up
Language (HTML).
HTML
at a Crossroads
HTML and the World Wide Web in general are currently in a stage
of development similar to that of the desktop publishing revolution.
Still working to reach maturity as a standard, HTML is feeling
the same growing pains that early word processing programs did-as
more users flock to HTML, there is a growing need to standardize
it and make it less complex to implement.
These days, word processors are much more intuitive than they
were 15 years ago. There are fewer codes and special keystrokes
required to get something done. The applications have matured
to the point where most of the low-level formatting is kept hidden
from the user of the application. At the same time, the printed
page is now more completely mirrored on the computer screen, with
accurately represented fonts, emphasis, line breaks, margins,
and paragraph breaks.
Although programs are quickly being developed to offer similar
features for HTML development, these tend to be less than ideal
solutions. Currently then, anyone who decides to learn HTML is
going to have to know some codes, memorize some syntax, and develop
pages for the World Wide Web without the benefit of seeing all
the fonts, emphasis, and paragraph breaks beforehand.
But anyone who has had any success with word processing programs
of ten or 15 years ago (or desktop publishing programs as recently
as five years ago) will have little or no trouble learning HTML.
Ultimately, you'll see that HTML's basic structure makes a lot
of sense for this emerging medium-the World Wide Web. And, as
with most things computer-oriented, you'll find that once you've
spent a few moments with it, HTML isn't nearly as difficult as
you might have originally imagined.
HTML
is not a Programming Language
There's nothing I'd like more than to say: "Yes, HTML is
a very difficult programming language that has taken me years
to master. So I'll have to charge $75 an hour to develop your
Web pages for you." Unfortunately, it's simply not the case.
As I've already hinted, creating an HTML document is not much
more difficult than using a ten-year-old copy of WordPerfect with
the Reveal Codes setting engaged.
Tip
Remember the definition of HTML: Hypertext Mark-up Language. In HTML itself, there is no programming-just the "marking up" of regular text for emphasis and organization.
In fact, I prefer to call people who work with HTML "designers"
or "developers," and not programmers. Actually, there's
only limited design work that can be accomplished with HTML (especially
the most basic standards of HTML), and anyone used to working
with FrameMaker, QuarkXPress, or Adobe PageMaker will be more
than a little frustrated. But the best pages are still those created
by professional artists, writers, and others with a strong sense
of design.
As Web page development matures, we are starting to see more concessions
to the professional designers, as well as an expansion into realms
that do require a certain level of computer programming expertise.
Creating scripts or applets (small programs) in the Java language,
for instance, is an area where Web page development meets computer
programming. It's also a relatively distinct arena from HTML,
and you can easily be an expert in HTML without ever programming
much of anything.
The basics of HTML are not programming, and, for the uninitiated
in both realms, HTML is much more easily grasped than are most
programming languages. If you're familiar with the World Wide
Web, you've used a Web browser like Netscape, Mosaic, or Lynx;
and if you have any experience with a word processor or text editor
like WordPad, Notepad, SimpleText, or Emacs, then you're familiar
with the basic tools required for learning HTML.
A Short
HTML History
HTML developed a few years ago as a subset of SGML (Standard
Generalized Mark-up Language) which is a higher-level mark-up
language that has long been a favorite of the Department of Defense.
Like HTML, it describes formatting and hypertext links, and it
defines different components of a document. HTML is definitely
the simpler of the two, and although they are related, there are
few browsers that support both.
Because HTML was conceived for transmission over the Internet
(in the form of Web pages), it is much simpler than SGML, which
is more of an application-oriented document format. While it's
true that many programs can load, edit, create, and save files
in the SGML format (just as many programs can create and save
programs in the Microsoft Word format), SGML is not exactly ideal
for transmission across the Internet to many different types of
computers, users, and browser applications.
HTML is more suited to this task. Designed with these considerations
in mind, HTML lets you, the designer, create pages that you are
reasonably sure can be read by the entire population of the Web.
Even users who are unable to view your graphics, for instance,
can experience the bulk of what you're communicating if you design
your HTML pages properly.
At the same time, HTML is a simple enough format (at least currently)
that typical computer users can generate HTML documents without
the benefit of a special application. Creating a WordPerfect-format
document would be rather difficult by hand (including all of the
required text size, fonts, page breaks, columns, margins, and
other information), even if it weren't a "proprietary"-that
is, nonpublic-document format.
HTML is a public standard, and simple enough that you can get
through a book like this one and have a very strong ability to
create HTML documents from scratch. This simplicity is part of
a trade-off, as HTML-format documents don't offer nearly the precision
of control or depth of formatting options that a WordPerfect-
or Adobe PageMaker-formatted document would.
Marking
Up Text
The most basic element of any HTML page (and, therefore, any page
on the Web) is ASCII text. In fact, although it's slightly bad
form, a single paragraph of regular text-generated in a text editor
and saved as a text file-can be displayed in a Web browser with
no additional codes or markings (see fig. 1.1). An example of
this might simply be:
Figure 1.1 : Text is so basic to HTML that it can be displayed in a Web browser with no additional commands or codes.
Welcome to my home on the World Wide
Web. As you can see, my page isn't
completely developed yet, but there were some things I simply
had to say
before I could get anything else done. My name is Emmanuel Richards,
and
I'm a real estate developer located in the San Fernando Valley.
If you'd
like, you can reach my office at 555-4675.
Note
Although possible, you would never want to display plain text on the Web without conforming to certain HTML conventions, which are explained in Chapter 6, "Creating a Web Page and Entering Text."
Remember that HTML-formatted documents aren't that far removed
from documents created by a word processing program, which are
also basically text. Marking up text, then, simply means you add
certain commands, or tags, to your document in order to
tell a Web browser how you want the document displayed.
One of the most basic uses for HTML tags is to tell a browser
that you want certain text to be emphasized on the page. The HTML
document standard allows for a couple of different types of emphasis
including explicit formatting, where you choose to make something
italic as opposed to bold, or implicit formatting, where it's
up to the browser to decide how to format the emphasized text.
Using part of the example above, then, an HTML tag used for emphasis
might look something like this:
Welcome to <EM>my home</EM>
on the World Wide Web.
In this example, <EM>
and </EM> are HTML
tags that tell the Web browser which text (in this example, my
home) is to be emphasized when displayed (see fig.
1.2).
Figure 1.2 : HTML tags can be used to mark certain text for emphasis.
The browser isn't just displaying regular text; it has also taken
into account the way you want the text to be displayed according
to the HTML tags you've added. Tags are a lot like margin notes
you might make with a red pen when editing or correcting term
papers or corporate reports. After you've entered the basic text
in a Web document, you add HTML mark-up elements to tell the browser
how you want things organized and displayed on the page.
You'll learn more about the specific types of tags in Chapter 6,
"Creating a Web Page and Entering Text," but for now,
the most important distinction is between text and HTML tags.
All HTML documents will be basically text, as are all word processing
documents and most desktop publishing documents. The only difference,
then, is how the text is described for display on the screen (or,
in many cases, for a hard copy printout).
In most word processing documents, the "mark up" that
describes the emphasis and organization of text is hidden from
the user. HTML, however, is a little more primitive than that,
as it allows you to manually enter your text mark-up tags to determine
how the text will appear. You can't do this with an MS Word document,
but, then again, MS Word documents aren't the standard for all
Web pages and browsers on the Internet!
Who
Decides What HTML Is?
It's difficult to pin down exactly who is responsible for the
HTML standard and its continued evolution. While what may be the
most important question is who uses HTML, and how they use it,
a number of groups exist to monitor, brainstorm, and try to pin
down the standards as they evolve.
The HTML Working Group
The HTML standard is maintained and debated by a group called
the HTML Working Group, which, in turn, is a creation of the Internet
Engineering Task Force. The Working Group was charged in 1994
with the task of defining the HTML standard that was in widespread
use on the Web at the time (known as HTML 2.0), and then submitting
proposals for future standards, including the HTML 3.0 standard.
Up until the spring of 1996, the Working Group seemed to be the
bearer of the basic standard for HTML around the world, while
others work to agree on standards for other Web-oriented technologies
that have a cursory relationship-like graphics formats, digital
movies, sounds, and emerging Web languages such as Java and VRML
(Virtual Reality Modeling Language). Now, nearly all responsibility
for future Web development will most likely fall to an industry
cooperative called the W3 Consortium.
The World Wide Web Consortium
HTML was originated by Tim Berners-Lee, with revisions and editing
by Dan Connolly and Karen Muldrow. Up until the time when the
Working Group took over responsibility for the standard, it was
largely an informal effort.
Still very much involved in the evolution of the standard is Tim
Berners-Lee, who now serves as director of the World Wide Web
Consortium (W3C)-a group of corporations and other organizations
with an interest in the World Wide Web. The group is run by the
Laboratory for Computer Science at MIT, and includes members such
as AT&T, America Online, CompuServe, Netscape Communications
Corp., Microsoft Corp., Hewlett Packard, IBM, and many others.
Here, member organizations get together to iron out differences
over Web-related standards and practices while working to maintain
some level of standardization between their products. Corporate
self-interest can sometimes get in the way, but it is definitely
of utmost importance to most of these organizations that their
products stay abreast of the most popular standards, and that
their customers are fully able to take advantage of the Web.
Individual Companies
and HTML
In the meantime, HTML continues to evolve, sometimes in spite
of standard-bearing organizations. As more and more commercial
companies take an interest in the HTML standard, it has become
increasingly difficult to know who, exactly, decides what HTML
will become in the future.
Some notable deviations from the standard are the extensions,
or additional commands, that Netscape Communications Corp. has
added to HTML 2.0 (see fig. 1.3). Only Netscape's browsers (and
those written to be compatible with Netscape's products) can view
all of these extensions, and some of them have yet to be recognized
by the HTML Working Group. Netscape can get away with this, though,
since it controls somewhere around 60 percent of the World Wide
Web browser market.
Figure 1.3 : Aside from being able to view most of the HTML standard tags recognized by the HTML. Working Group, Netscape Navigator can also display text in special ways.
With that sort of influence, Netscape can sway the hearts and
minds of members of the W3 Consortium to some degree-plans for
future HTML specifications often take into account the additions
made by companies such as Netscape.
Other companies, notably Microsoft, have also distributed Web
browsers-in Microsoft's case, the Internet Explorer-that offer
enhancements over the agreed-upon HTML standards, and acceptance
of those extensions by a majority of Web designers may further
sway groups like the HTML Working Group.
What is the IETF?
The Internet Engineering Task Force (IETF) is a fairly loose organization of people interested in affecting the growth and infrastructure of the Internet. It is the main group engaged in the creation of new Internet standards and specifications.
The first IETF meeting was held in January 1986 in San Diego, and drew 15 attendees. The IETF now meets in a variety of locations, including meetings held occasionally in Europe and elsewhere around the world. Meetings and participation are completely voluntary, and anyone can attend meetings, which are held three times a year.
Although there is no formal or legal power behind the specifications created by the IETF, they are often reasonable and useful enough that they are adopted by the Internet community as a whole. The Internet, perhaps more so than many other computing communities, relies on useful and widely available standards in order to reach the greatest number of people.
The IETF's role in the future of HTML is a little vague, since it seems that most Web-related development efforts have been shifted to the W3 Consortium, with the emphasis seemingly on cooperation between the competing corporate standards emerging on the Web.
Anyone can also join the IETF announcement mailing list or the IETF discussion list (ietf@cnri.reston.va.us). This is where the broadest Internet discussions are held (most working groups have their own mailing lists for discussions related to their work). To join the IETF announcement list, send an e-mail with the word subscribe in the body to ietf-announce-request@cnri.reston.va.us.
To join the IETF discussion list, send an e-mail with the word subscribe in the body to ietf-request@cnri.reston.va.us.
To join the discussion list for the HTML Working Group, send a blank e-mail message to www-html-request@w3.org.
Additional
Information on HTML Standards and Organizations
Most of the HTML standard bodies and organizations maintain an
active presence on the World Wide Web, and information about these
groups and their work can be found in many places.
For more on the World Wide Web Consortium, consult the W3C Web
site at http:/www.w3.org/. This site will probably be the
most useful as you continue to learn more about HTML and emerging
new standards.
For more information on the IETF, point your Web browser to the
URL http://www.ietf.cnri.reston.va.us/home.html. This is
the IETF's home on the Web, offering tons of links to related
projects as well as information about meetings and other Internet-related
groups.
To learn about the HTML Working Group, take a look at http://www.ics.uci.edu/pub/ietf/html/.
Here, you'll find a little about the history of HTML, who the
current members and officers of the Working Group are, and how
to contact the group.
Information about Netscape and Netscape's additions to HTML can
be found at http://www.netscape.com/.
Summary
HTML is a document format, somewhat like word processing or desktop
publishing formats, but considerably less complicated and based
on more open standards. Creating HTML programs isn't really programming-although
some programming can be necessary in other aspects of Web page
creation. There are a few different organizations that make it
their business to oversee the HTML standard, but the standard
can just as easily be affected by the software companies that
write Web browsers. The standard is also influenced very much
by what commands and layout features Web designers implement,
and what commands they ignore.
Review
Questions
Is HTML a programming language?
True or false. HTML documents can be created with nothing
more than a text editing program.
What other mark-up language is HTML based on?
What's the difference between explicit formatting and implicit
formatting?
True or false. You can directly edit a WordPerfect-format
document.
Is the HTML Working Group a subsidiary of the World Wide Web
Consortium?
Why is it important that HTML be a public standard?
How can individual Web designers affect the HTML standard?
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