major benefit of CSS is that it makes your website SEO friendly. The reason behind this is simple. The search engines spiders are actually very lethargic. They do not go through the bundles of HTML codes to get to the indexed codes. Font tags and tables make the HTML code very cumbersome; thus, reduce the accuracy of the results. If you use external CSS files to design and determine the design attributes; the HTML code will be clean and it will result to better search engine rankings. With some knowledge of CSS you will be able to change the code layout without destroying the actual visual layout. For instance, you could easily make the main content of your site to show up above the header or navigation menu in the code of your website; thus will help to show search engine crawlers the importance of your content. I personally saw a huge boost in rankings in fully CSS web sites. When I look at someone’s website that was built using old school HTML code with tags such as: TABLES, TD, TR, FONT and so on, I feel awkward and immediately convert that site to a fully table-less CSS layout. There are many tools on the Internet that shows the actual code over text ratio weight of your site. Do you know why? Because modern search engines such as: Google, Yahoo and MSN love light-weighted websites. They want to see your content; the text, not the code. With CSS everything is possible. You practically externalize excessive code into external file, thus leaving the actual page clean and simple.