[2007-11-27] Don't Get Banned for Paid Links!
Google has officially announced that selling links is a linking scheme and outlines what is considered bad for your site and what is considered acceptable when it comes to advertising on your blog.

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[2007-11-06] The Complete Guide to Using Words Correctly on Your Site
When optimizing your website, it is generally expected that your pages need to have certain keyword density to be ranked with the search engines.

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