www vs. Non-www?
The problem is that www is considered a sub-domain, just like: http://mail.yahoo.com or http://analytics.google.com.
Search engines consider subdomains to be a completely different web site. So, http://www.dauclair.com is a completely different site than http://dauclair.com in Google’s eyes.
This affects your SEO in two areas:
- If Google happens to index your site as both www and non-www, you may be penalized for duplicate content. Your site is essentially competing against itself.
- Google determines your PageRank, the importance of your site, by the number of inbound links your site has. So, if people are linking to www, but your site is indexed as non-www, you are missing out on all the inbound links pointing to your www site.
