(This page uses CSS style sheets)
"Hopefully, future Web innovations will emulate the example set by the Web Consortium in its work on CSS"
--Jakob Nielsen
Style sheets describe how documents are presented on screens, in print, or perhaps how they are pronounced. W3C has actively promoted the use of style sheets on the Web since the Consortium was founded in 1994. The Style Sheets Activity has produced two W3C Recommendations (CSS1 and CSS2) which are widely, although not consistently, implemented in browsers.
By attaching style sheets to structured documents on the Web (e.g. HTML), authors and readers can influence the presentation of documents without sacrificing device-independence or adding .
The easiest way to start experimenting with style sheets is to find a browser that support CSS. Discussions about style sheets are carried out on the www-style@w3.org mailing list and on comp.infosystems.www.authoring.stylesheets.
The W3C Style Sheets Activity is also developing XSL.
The fact that W3C has started developing XSL in addition to CSS has caused some confusion. Why develop a second style sheet language when implementors haven't even finished the first one? The answer can be found in the table below:
| CSS | XSL | |
|---|---|---|
| Can be used with HTML? | yes | no |
| Can be used with XML? | yes | yes |
| Can transform documents? | no | yes |
| Syntax | CSS | XML |
The unique features are that CSS can be used to style HTML documents. XSL, on the other hand, is able to tranform documents. For example, XSL can be used to transform XML data into HTML/CSS documents on the Web server. This way, the two languages complement each other and has synergy between them.
Both languages can be used to style XML documents.
CSS and XSL will use the same underlying formatting model and designers will therefore have access to the same formatting features in both languages. W3C will work hard to ensure that interoperable implementations of the formatting model is available.
If you are new to the subject, you may want to start by reading some press clippings on style sheets:
Cascading Style Sheets (CSS) is a style sheet mechanism that has been specifically developed to meet the needs of Web designers and users.
Where CSS1 is simple, DSSSL is advanced. DSSSL, an ISO standard, is a document tree transformation and style language with many adherents in the SGML community.
It's a mistake to put DSSSL into the same bag as scripting languages. Yes, DSSSL is turing-complete; yes, it's a programming language. But a script language (at least the way I use the term) is procedural; DSSSL very definitely is not. DSSSL is entirely functional and entirely side-effect-free. Nothing ever happens in a DSSSL stylesheet. The stylesheet is one giant function whose value is an abstract, device-independent, nonprocedural description of the formatted document that gets fed as a specification of display areas to downstream rendering processes.
-- Jon Bosak
DSSSL resources on the Web:
W3C has recently launched a Working Group to develop the eXtensible Style Language (XSL). XSL builds on DSSSL and CSS and is primarily targeted for highly structured XML data which e.g. needs element reordering before presentation. One feature of XSL is that it can be user-extended through the ECMAScript language. For more information on XSL see the W3C XSL resource page.
Dynamic HTML is a term used to describe HTML pages with dynamic content. CSS is one of three components in dynamic HTML; the other two are HTML itself and JavaScript (which is being standardized under the name EcmaScript). The three components are glued together with DOM, the component object model. Dynamic HTML is still in its infancy and current implementations are experimental.
The proposals are roughly in chronological order. They contain ideas that current proposals build upon, and serve as background material.
970922: The eit list archive no longer seems operational and we're looking for a new source for links below