Greater author control over appearance of text and its placement on the page Reduced clutter of multiple opening and closing tags on individual text elements Simplified modification of page design through style editing Elimination of the need for clumsy HTML workarounds to achieve basic layout effects Great improvement of the design potential for HTML pages without introducing a large number of new proprietary tags, or compromising the ability of other browsers to effectively display the document text HTML was not designed as a presentational language. As the web evolved, this structural started evolving into a presentational language. Consequently, large parts of HTML 3.2 and HTML 4.0 are devoted to presentational elements. However, the makes the documents far less useful. A FONT tag is of no use to a speech-synthesis browser, it has no way of knowing that the text is any different from any other text.
Structured markup is easier to maintain.
CSS1 lacks media types. CSS1 is primarily a screen-device language, intended to used to put content onto a computer monitor. Implementation - Browser support was poor. IE 4.0 and 5.x are getting better. Netscape Navigator 4.7 is not significantly better at supporting style sheets than was version 4.0.