Cascading Style Sheets, or CSS, is an HTML addition that allows the designer to control various web page design parameters by pre-defining them in the < head > tag either by referencing to an external CCS file or by placing the CCS information for that particular page directly in the < head > tag.

CSS massively decreases download time and can save design time as well if the same CSS file is used throughout the site. As far as search engines are concerned, using an external CSS file removes code bloat. You can also use CSS files to give the engines what they want such as the hefty and ugly < H1 > tags without having to compromise on the way the site appears to the human viewer. Using CSS to define margins, fonts, link appearance, colours, and placement means that you can feed the engines what would normally be a Big, Dumb and Ugly page without it appearing that way to humans.

Please note that we are not talking about spam here. All we are saying is that you can set the < H1 > tag in CSS to look like small, bold type while the engines will still treat it with all the respect that text in the (traditionally horrid looking) < H1 > tag deserves.

What you should NOT use CSS for is hidden layers in an effort to get more keywords in without having to have them in the visible text, otherwise known as spam. Even if the engines don't get you (and they eventually will) your competitors are keeping a sharp eye out and they (or their promotions company) will report it. Hidden layers are a big no-no so don't even think about it.

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