Datasheet

The next section takes a look at the independent organization that makes recommendations about how

CSS, as well as a variety of other web-specific languages, should be used and implemented.

Who Creates and Maintains CSS?

Creating the underlying theory and planning how cascading style sheets should function and work in a

browser are tasks of an independent organization called the World Wide Web Consortium, or W3C. The

W3C is a group that makes recommendations about how the Internet works and how it should evolve. I

emphasize should, because the World Wide Web Consortium has no control over the implementation of

the standards that it defines. The W3C is comprised of member companies and organizations that come

together to create agreed-upon standards for how the web should function. Many prominent companies

and organizations are W3C members, including Microsoft, Adobe, The Mozilla Foundation, Apple,

Opera Software, and IBM. The W3C oversees the planning of several web languages including CSS,

HTML, XHTML, and XML, all of which are mentioned in this book.

CSS is maintained through a group of people within the W3C called the CSS Working Group. The CSS

Working Group creates documents called specifications. When a specification has been discussed and

officially ratified by W3C members, it becomes a recommendation. These ratified specifications are

called recommendations because the W3C has no control over the actual implementation of the language.

Independent companies and organizations create that software.

The specifications created by the W3C are not limited only to web browsers; in fact, the specifications

can be used in a variety of software, including word processor and spreadsheet applications, as well as

by different types of hardware devices, such as PDAs and cell phones. For that reason, the software

implementing a specification is referred to by the W3C as the user agent, which is a generic term that

encompasses all the different types of software that implement W3C specifications.

The W3C merely recommends that a language be implemented in a certain way to ensure that the lan-

guage does what is intended no matter which operating system, browser, or other type of software is

being used. The goal of this standardization is to enable someone using the Netscape browser, for

example, to have the same Internet experience as someone using Internet Explorer, and likewise, for

developers to have a common set of tools to accomplish the task of data presentation. Were it not for

web standards, developing documents for the web might require an entirely different document for a

given user agent. For example, Internet Explorer would require its own proprietary document format,

while Mozilla Firefox would require another. Common community standards provide website develop-

ers with the tools they need to reach an audience, regardless of the platform the audience is using.

As I write this, CSS comes in four different versions, each newer version building on the work of the last.

The first version is called CSS level 1, and became a W3C recommendation in 1996. The second version,

CSS level 2, became a W3C recommendation in 1998. The third version, CSS level 2.1, is currently a

working draft, downgraded from a candidate recommendation since I wrote the first edition of this

book in 2004. A candidate recommendation is the status the W3C applies to a specification when it feels

the specification is complete and ready to be implemented and tested. After the specification has been

implemented and tested by at least a few of the member companies, the candidate recommendation is

then more likely to become a full recommendation. A working draft is the status the W3C applies to an

ongoing work, which is subject to change. The fourth version of CSS is called CSS level 3, and many por-

tions of it are still in development. Although portions of CSS are officially subject to change by the W3C

Part I: The Basics

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