Every journey starts with a single step: the Web past
It is hard to find a book about Hypertext Markup Language (HTML) and the Web
these days without having it start off with a history section. We used to wonder why
that was the case. To understand why the web standards approach to building websites
is the best way to go, you have to know about the progression of the World Wide Web
as it has evolved to become what it is today. The World Wide Web has very technical
roots, and the trouble (or charm) with most techies is that they like to customize—
change things until those things are perfect in their minds. They cannot follow what
everyone else is doing; they need to add their own flavor to it.
The Web started its life as a research project at CERN (the European Organization for
Nuclear Research) in Geneva, Switzerland. At the time, a researcher there by the name
of Tim Berners-Lee was looking for a way to quickly and easily share research findings
with his peers and organize information in such a way that it would be easy to archive
and retrieve. Although the process was started in the early 1980s, it wasn't until 1990
that Berners-Lee produced the first web server and web browser (which was called Worldwide Web, the origin of the name).
In 1992, the Web began to hit the mainstream when the National Center for Super computing
Applications (NCSA) in the United States released Mosaic, which was capable of
displaying text and graphics simultaneously. Mosaic gave non-scientists easy access
over the Internet to documents created using HTML, what we now call web pages.
Encouraged by this early success, one of Mosaic’s creators, Marc Andreesen, left the
NCSA and started Mosaic Communications Corporation. This later became Netscape Communications Corporation, creators of Netscape Navigator, which was the first
commercial browser and the web standard-bearer through most of the 1990s.
A company called Spyglass licensed NCSA’s source code and eventually released Spyglass Mosaic
(though on a newly developed code base). This became the basis for Microsoft
Internet Explorer and set the stage for the battle for browser supremacy between Netscape and Microsoft.
Just prior to the start of the “browser wars” of the 1990s, Berners-Lee recognized that
without some sort of governance, the World Wide Web would experience great challenges as
competing web browsers introduced new features. One of the ways to get someone to pick your product over your competition was to offer a bunch of really cool features that the other guy didn’t offer. He foresaw
compatibility problems emerging as competing companies introduced their own tags in order to add
features to the World Wide Web. HTML was the glue binding the Web together, and some central
body would need to oversee its evolution in order to maintain a high level of interoperability.
Microsoft gave away Internet Explorer as part of Microsoft Office, bundled it with Windows, and made
it available as a free download for all its various operating systems, as well as for Macs.
Microsoft was a late starter in the browser market, and by the time it entered the game in 1995, Netscape had an estimated 80 percent market share. The tides rapidly turned, however,
and by the time Netscape was acquired by America Online in 1998, Microsoft had
approximately half of the web browser market. By 2002, Internet Explorer reached its
peak with an estimated 96 percent of web surfers using Internet Explorer. In fact,
Microsoft so thoroughly thrashed Netscape in the browser wars that they ended up
in a contracted lawsuit that eventually led to a finding of Microsoft’s abuse of monopoly power in the marketplace. Figure 1-1 shows a timeline of major browser releases, starting in the early 1990s.
Figure 1-1. Timeline of major browser releases
The browser wars were an incredibly difficult time for web developers as manufacturers raced to do
their own thing. Versions 3 and 4 of the major browsers often had developers coding two entirely
separate versions of their websites in order to ensure compatibility with both Internet Explorer and
Netscape. Although web standards existed, most browsers only really supported the basics and relied
on competing (and incompatible) technology to do anything advanced, which is what web developers
wanted to do.
Netscape, although owned by a fairly major company, started to stagnate. Netscape open sourced its
code base, and the Mozilla project was born. The Mozilla community took off with the code and
started to really implement standards support in a new way through a complete rewrite of the rendering
engine. Although Mozilla was, early on, based on Netscape Navigator, the tables rapidly turned,
and subsequent releases of Netscape became based on Mozilla.
The Mozilla project has forked into a number of new browsers, most notably Firefox, which has
sparked a new browser war with Microsoft. Yet this time, the battle has had a positive effect. Microsoft
had all but stopped working on Internet Explorer once it released version 6. When Firefox hit the
scene with near-perfect support for web standards, it became an immediate hit and gained a great
deal of popularity with both the web cognoscenti and the general public. It seems as though Microsoft
had no choice but to improve its web browser, and the result is Internet Explorer 7.
A number of other players emerged in the web browser marketplace, offering competition to the
major players. Notably, Opera has always touted excellent support for web standards as one of its
major selling features. It has caught on to some degree (2 percent as of January 2008) and is also
focusing in a large part on mobile devices.
Safari by Apple Computer hit the scene in 2003 and quickly became one of the most popular choices
for Mac users because it integrates well with the operating system and is generally faster than competing
browsers on the Mac. Apple introduced a Windows version in 2007, but that product has yet to
leave beta. One of the most unique qualities of Safari is that even with its minor updates (so-called
point releases), Safari has improved its support of web standards, something that is often relegated to
major releases among other browser manufacturers.
Then there were standards: the Web now
Could you imagine if each TV channel was broadcast in either PAL or NTSC in each country, requiring
viewers to use a different TV set depending on what they wanted to watch? Similarly, imagine writing
a research paper, running a search on Google, and then having to open each of the results returned in
a different web browser. The first link is Internet Explorer, the second and third are Netscape . . . OK,
now back to Internet Explorer . . . Yet, this is pretty much how things worked in the late 1990s. One of
the most common sights on the Web were these wonderful (heavy sarcasm here) graphic badges
telling visitors that this website is “Optimized for Internet Explorer” or “Best Viewed with Netscape
Navigator” (see Figure 1-2).
Figure 1-2. Internet Explorer and Netscape
Navigation “get it now” buttons
When we talk about web standards, we’re generally referring to the big three players on the Web:
HTML (or XHTML), Cascading Style Sheets (CSS), and JavaScript. The World Wide Web Consortium
(W3C) maintains many other standards, such as Scalable Vector Graphics (SVG) for vector graphic
display, Portable Network Graphics (PNG) as a way to compress bitmap graphics, and Extensible
Markup Language (XML), which is another markup language, similar in a lot of ways to HTML.
While HTML/XHTML is all about structuring your document, CSS handles formatting and displaying
your various page elements. Because they’re two separate pieces of technology, you can separate
them (by separating content from display). The early versions of HTML (prior to the release of CSS)
were intended to be everything to everyone. The ability to specify colors and fonts was built right in
by specifying the attributes of various tags. As sites began to grow in size, however, the limitations of
going this route quickly became apparent.
Imagine that you have put together a website to promote this book. Throughout the site, which covers
all the chapters in detail, there are quotes from the book. To really make these quotes jump off the
screen, you are going to put them in red and make them a size bigger. In the good old days, your code
would look something like this:
<font size="+1" color="red">In the good old days, å
your code would look something like this:</font>
With a little XHTML and CSS, the code could look like this (note we said “could” because there are
multiple ways of doing things—this is a good, structurally relevant example):
<blockquote>In the good old days, å
your code would look something like this:</blockquote>
And then in a separate CSS file (or at the top of your HTML document—but again, that’s just another
option) that you would import/link to on pages of your website, there would be something like this:
blockquote { font-size: 1.5em; color: red; }
So what? They both do the same thing. Web browsers will display the quotes in red and make them
nice and big. One of the immediate advantages, however, is in making updates. As we mentioned previously,
you are liberally quoting the book throughout the entire website, chapter by chapter. By the
end of the project, you discover that you have used more than 300 quotes! The only problem is that
we, as the authors (and your client), absolutely hate red text. It makes us so angry. So, we’re going to
ask you to change it everywhere.
What would you rather do: update one line in the CSS file or open every page on the site and change
the color attribute to blue? (Blue is much more calming.) Three hundred quotes—you’re billing by
the hour—so that’s not so bad. It’s maybe an extra half day of work. Now extrapolate this example to
something like the New York Times where there are quite likely millions of quotes throughout the
entire website. Are you still keen to go change every font tag?
You’re thinking to yourself, “My software can do search and replace.” This is true. We were once asked
to update a department website at an organization where we worked. The website had about 16,000
pages, and by the end of a week, our search and replace still hadn’t finished. We’re not that patient.
Are you?
Additionally, CSS has evolved and is still evolving, allowing designers and developers to do more and
more in terms of the layout and appearance of their pages. Using CSS you can position any element
anywhere you like on a page. Although you could probably accomplish the same thing with a
table-based layout, it would probably take you a considerable chunk of code including settingabsolute heights and widths of table cells. One thing you can’t do, however, is overlap a pair of table
cells, which is something that’s extremely easy to do using CSS.
The upcoming release of CSS (version 3) has even more formatting options baked in. You will be able
to specify multiple background images for an element, set the transparency of colors, allow certain
elements to be resized on the fly, and add drop shadows to text and other elements on the fly. Check
out the W3C website or, for a slightly more human-readable form, http://www.css3.info for more
information.
The provided example is a pretty simple representation of what you can do using XHTML and CSS. If
you head over to the CSS Zen Garden (http://csszengarden.com/) and click through some of the
examples there, you can gain an appreciation for the level of control you can have by tweaking the
CSS for a website. CSS Zen Garden uses the same markup for every example (the XHTML part stays the
same on every page). The only thing that is different on each page is the CSS file that is included, as
well as any supporting graphics (see Figure 1-3, Figure 1-4, and Figure 1-5).
Figure 1-3. One example from CSS Zen Garden (http://www.csszengarden.com). Each of these pages uses
the same XHTML markup; each page is just styled differently using CSS and images.
Figure 1-4. This is the same page as shown in Figure 1-3 but styled using an alternate style sheet at the
CSS Zen Garden
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