Marko Saric at HowToMakeMyBlog.com points out that the following website URL’s may seem like they are the same page to you, but to a search engine they might actually seem like two different pages:
http://yourblog.com
http://www.yourblog.com
What’s the problem with that? Search engines may think www.yourblog.com and yourblog.com are two different blog sites. As a result, you won’t get the full SEO (search engine optimization) benefits that you should. In plain English, your site may not rank as high in the search engines as it would otherwise. The solution is to set up a permanent redirect (technically called a “301 redirect”) between these sites. Once you do that, you will get full search engine credit for your work on these blog sites and it will improve your search engine optimization and the SEO rankings.
Go to Marko’s article Fix Your Permanent Redirect To Optimize Your Blog SEO to get the code to fix this. When this code is saved to your index.php, all your visitors will be redirected to www.yourblog.com even if they enter yourblog.com in their browser address bar.
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