After six years, CSS2 promises to be much simpler to use.
What is it?
Cascading Style Sheets (CSS) offers a way of adding styles, such as
fonts and colours, to web documents. CSS enables presentation to be
separated from content to cope with the different platforms on
which web pages are displayed.
According to website accessibility expert Jakob Nielsen, "Web style
sheets are cascading, meaning that the site's style sheet is merged
with the user's style sheet to create the ultimate presentation.
"These differences make it important that web style sheets are
designed by a specialist who understands the many ways the result
may look different than what is on his or her own screen."
Style sheets may be external, meaning they can be specified once
and applied to all the documents on a website, or embedded within a
particular document.
Where did it originate?
CSS began life in 1994 at Cern, the cradle of the web, when H†kon
Wium Lie published the first draft of cascading HTML style sheets.
He had the backing of HTML3.0 architect Dave Raggett, who realised
that HTML needed a purpose-built page description mechanism. In
February 1997 CSS got its own World Wide Web Consortium (W3C)
working group. The first commercial browser to support CSS was
Microsoft's Internet Explorer 3.
What is it for?
Different style sheets arrive in a series, or cascade, and any
single document can end up with style sheets from multiple sources,
including the browser, the designer and the user. Cascading order
sorts out which set of rules are to influence the
presentation.
What makes it special?
CSS gives a greater level of control over how work is presented
than with HTML.
How difficult is it to master?
Style sheets can either be hand-written using a text editor or with
one of the growing number of web design tools which support CSS.
The W3C CSS home page has a list of these tools which include
Dreamweaver, Adobe Golive and Homesite. You do not need to know CSS
syntax but those who do can fine-tune their style sheets.
Where is it used?
CSS is currently the most widely supported way of styling web
documents.
Not to be compared with...
Cascading system failures - the impact of the collapse of one part
of an infrastructure on the next.
What systems does it run on?
CSS is supported by most current browsers and web design
tools.
Not many people know that...
"CSS is now being taken up, but HTML is in danger again," said Bert
Bos, W3C's style sheet activities co-ordinator.
"Javascript is the worst invention ever. At first we though we
could replace Javascript with style sheets and Java for
applications, but Java is not so great for simple programs."
What is coming up?
CSS3, six years in the making, promises to be much simpler to use
than CSS2/.2.1.
Training
You should not need to spend much money learning CSS. The World
Wide Web Consortium has comprehensive links to tutorials, how-to
articles and books by the likes of H†kon Wium Lie, Bert Bos, Dave
Raggett and Jakob Nielsen.
Most date back a few years, but remember that the current level,
CSS2, has been around since 1997.
www.w3.org/Style/CSS/learningRates of pay
CSS is used by web designers but also sought in software
developers, testers and technical authors. Rates vary accordingly.