If you advertise your website on Google AdWords, or MS Bing/Yahoo Adds, chances are that you found out that you can spend a lot of money on these PPC (Pay Per Click) campaigns without getting reasonable return.
The fact of the matter is that long tail keywords ( longer more specific keywords) convert better than a short one (as catchy as it my seem) and there are a lot of longer tale keywords available.
Several studies found out that long tail keywords have a much higher conversion rate than single word keywords.
Long tail keywords keywords that consists of 4 or more words.
This is true today as it was when the following article was published. :http://seo-genie.blogspot.com/2010/02/google-adwords-negative-keywords more keywords.html