Separating the Content from its Presentation

The main idea behind the concept of separating the(Open Financial Exchange) is a close relative of XML
content from its presentation is to allow websitethat has been widely used by financial institutions
developers a useful framework to develop theirwho have been using Electronic Data Interchange
website giving them the ability to change the(EDI) systems to transmit orders and invoices over
website's appearance whenever they like withoutprivate networks, intranets and the internet for
needing to redo the content structure. This article willseveral years.
explain the rationale behind separating content fromThe need to present the content in a standard way
presentation.that separates it from any design elements was so
Don't get me wrong, there isn't just one method forurgent that for the first time in software
implementing this concept. More than that, since thedevelopment history all the three major players (SUN,
introduction of technologies such as CGI, ASP, andIBM, and Microsoft) actually agreed with each other
PHP that allow web developers to generate dynamicand XML become a standard almost overnight and
web pages, a lot of companies have found creativewas adopted by many content providers and news
ways to develop their website applications using thisagencies.
concept as their foundation.Yet the concept was not fully implemented. CSS
Over the past few years, the internet communityhandles the styling aspects while XML handles the
has been trying to create a set of standards fordocument content. What about the webpage layout?
creating web sites. A new technology called CSS orNew websites are been published each day by
Cascading Style Sheets has been introduced. There isthousands. Every day millions of new web pages are
nothing actually new in the way CSS handles a webbeing added to the internet's global database.
page's presentation. CSS allows the developer toWebmasters have found that changing the page
define a style for each html tag element. This isbackground color or the font color might not be
similar to the method developers (programmers)enough to keep their website fresh and polished to
used in the old days when they attached a variablecompete with other new websites. However,
to each html tag defining its style. The majorchanging the website layout can sometimes involve a
difference is that CSS style definitions can belot of effort because it involves modifying the web
interpreted by most of the existing browserspage source code. XSL was introduced to solve that
available while in the older method the dynamic webissue. Consider XSL a set of rules that can describe a
page engine performs the interpretation.web page layout. Combine it with XML (and optionally
The internet standards organization W3C haswith CSS) you will get a valid html file.
encouraged the use of CSS by enhancing its ability toXSL is very similar in its mechanics as any other
control the web page's look and feel. New styledynamic web page generator. Beside the fact that
options have been added to the CSS specificationsXSL is platform independent, its biggest advantage is
that have not been added to the HTML descriptionthat it can be processed on the client side. The web
language. There's no doubt that this was a smartserver sends the client the content using XML format
move. It's forced web developers to use CSS toand the layout definition using XSL format. By doing
achieve an attractive web page that also supportsthat, the load on the web server's CPU is reduced
the principle of content separation. Unfortunately CSSallowing it to perform other tasks more quickly.
did not find its way into the internet mainstreamHowever, XSL was not adopted by all the major
easily because of compatibility issues with most webweb browsers. So unlike XML, XSL has not found its
browsers. These days CSS is widely supported byway to the market easily.
most of the major web browsers, while CSS2, anBefore you run back to your desk and start
enhanced version of CSS still has serious compatibilityredesigning your website according to these
issues.magnificent standards, you should be aware that
Obviously, the separation of content from itsthose technologies are really not needed most of the
presentation deals not only with the styling aspects,time. In fact, using them unnecessarily can cause
but also with browser compatibility issues. The stylingperformance problems. CSS usually will not cause
aspects were the first to be handled by webyour system to slow down. Just try to keep your
developers and web designers. As the complexity ofCSS file as small as possible. Many web developers
information technology (IT) systems becomemaintain large CSS files with lots of unused style
increasingly more difficult to maintain, the internetdefinitions. Deciding to work with XML is a serious
community is looking for a solution that will become adecision. If your website generates dynamic web
standard so that content can be easily be managed.pages supported by databases like MySQL, adding
One goal for this standard is to define a "language"additional XML functionality will definitely reduce your
that IT systems can "talk" with each other andwebsite performance. Sometimes you won't have a
exchange information. Large corporations havechoice and will need to upgrade your hardware to
historically used many different software platforms inmaintain your website's performance. There is no rule
their networks to conduct business. Internet basedof thumb for this issue. The decision should be based
applications can provide a single platform that can acton each system and its engineering demands. My
as an intermediary between all of these differentadvice to you is to think two steps ahead. Try to
systems and allow communication between them.predict what kind of future services your website will
XML (Extensible Markup Language) has been adoptedbe providing. Plan your website properly at stage one
as a standard to present the content itself. OFXand save yourself lots of effort later.