Is it Right to Use Canonical Tag to Set Preferred URL

Hi everyone,

I have already set preferred URL (with www) in Google Webmaster tools.

Do I still need to place <link rel="canonical" href="http://www.mynewsite.com" /> in the home page to tell search engines that this is my preferred url not the other versions.

Others versions may be these:
"http://mynewsite.com"
"http://www.mynewsite.com/index.html"
"http://mynewsite.com/index.html"

I think the best way is to use .htaccess file.

Using the canonical tag should work just fine to set this page as ur perferred url.

i always use canonical tag.