In the early days of the internet, everyone assumed that you MUST have the www in front of a domain name for it to work properly. As it happens, the www is just a way of indicating a “subdomain” of your main root domain. The root domain is always the domain name “naked” without the www, ie. http://askjoanne.com vs. http://www.askjoanne.com
I used to be a proponent of always using the www when identifying a domain name. This was partly because it was the most familiar format to people, and also because, if you precede your domain name with www in almost any email program, it will be automatically turned into a live link to your website. Lately, however, I have changed my tune and prefer to let my domain names go naked… without the www subdomain in front.
It really doesn’t matter which you decide to use, but you do need to decide. Since the search engines see pages http://askjoanne.com/what-askjoanne-does/ and http://www.askjoanne.com/what-askjoanne-does/ as 2 DIFFERENT pages, they can actually filter your site for what they consider to be “duplicate” content. Also, in getting links to your site, you want to make sure that all links are consolidated and go to the same domain (www or non-www), otherwise you “split” the strength and value of incoming links to your site across 2 different pages.
There are two steps to making sure you have a single primary domain name in use. Set your preferred domain name in Google Webmaster tools:
The next step is to setup a 301 redirect so that all traffic goes to one version of the site or the other, but not to both.
Have you set your preferred domain? If not, you should. Questions? Ask Joanne.