We prefer to link to stylesheets using @import because Netscape 4 doesn't understand it and therefore won't apply its half-assed implementation to it. This doesn't prevent NN4 from recognizing inline styles, though.

A chief caveat in working with CSS is the flawed support found in IE 6. Some view hacks as the solution (a la the days of JavaScript) whereas others prefer to define their selectors so explicitly as to make misinterpretation impossible. For example, whereas most browsers recognize body {margin:0} as equivalent to the margin attribute of the body tag, Opera does not and prefers {padding:0} for this effect. Declaring body {margin:0; padding:0;} resolves this problem for all browsers.

More important is the extent to which IE 6 does not support CSS 2 spec, which is why some of the cleverer dynamic menu layouts (which would end DHTML as we know it) are not as popular. It is hoped that Microsoft will bend to supporting CSS 2 fully, but until there's an IE 7 we won't know.

What we do know is that modern browsers respect DTDs and base their conformance on those declarations. People who edit valid XHTML files and insert HTML 3/4 spec code (ALL CAPS, unclosed tags, etc.) may be in for a surprise when the code hits the browser.

CSS is a balancing act of establishing display rules for tags, spans and/or blocks. Mercifully there are plenty of online resources for the beginner which demonstrate the concepts and slowly guide you into the pitfalls.