By default your hosting settings are set to use no www when your account is created. Any traffic sent to your domain with www for ex. www.yourdomain.com is redirected to yourdomain.com. If you want to alter this behavior you can do so in your control panel.
1. On your domains main settings page click Hosting Settings.
2. On the following page you will see the section Preferred domain
You can adjust this as you like. Remember if you allow both www and no www you may incur duplicate content penalties from search engines.
