Cascading style sheets (CSS) are a relatively new, and therefore still relatively little used extension of HTML. The CSS concept is, however, attractive, as it allows page authors to conveniently control the presentation of their pages without compromising their structure. HTML style sheets work in many ways like styles in word processors: the appearance of all HTML tags can be manipulated centrally with styles. In other word, individual HTML tags for headings, lists, quotations, etc., are left intact and will still be displayed properly with browsers that do not support styles. However, a distinct difference is that style sheets do not make HTML a desktop publishing language. They give more control over how documents are presented in a browser, but the authors cannot dictate the presentation fully because users have (cascading) style sheets of their own to adjust for human or technological handicaps (poor vision, colour blindness; unusual screen resolution and limited colour display capacity of monitors).
At the initial stages of style concept development, advanced browsers had their own proprietary codes and interpreted pages using style sheets differently. Fortunately, the main developers have recently agreed to support a single CSS standard. The experience with word processors shows that the concept of style sheets - as powerful and simple as it is - is a very difficult one and that organizations seldom have policies to use them, which makes it the single most under-utilized feature of modern word processors. Most organizations have a proliferation of document formats, sometimes exceeding the number of employees. Centralized, well-designed style sheets are a powerful tool for the Web page authors and site managers, and they should be considered early on as a long-term solution for creating a uniform look to Web site and for rationalizing the maintenance work. Read more about style sheets at http://www.w3.org/Style/
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