Preferred URL
Google Webmaster Tools allows you to be closely connected with Google. This is important since Google is the major search engine player, and is where a bulk of traffic to your site will come from.
Determine Website URL
It is important to know your preferred website URL. This can either be www.yourwebsite.com or yourwebsite.com. It doesn’t matter which one is preferred, but it is important to setup your Google accounts with the preferred URL.