If I visit my home page by entering example.com into my browser's address bar, my home page URL is example.com.
If I visit my home page by entering www.example.com into my browser's address bar, my home page URL is www.example.com.
If I visit my home page by clicking on an internal link, my home page URL is www.example.com/index.php.
Isn't this bad for the search engines?
Shouldn't I redirect all traffic to www.example.com?
If so, how do I do it in an SEO-friendly way?
Any help will be much appreciated.