Which http format should I publish and generate links for my website?http:// or www?

Which one performs best for seo?I am currently going to launch a website,but I am also looking for its SEO which is to compete with 135000 searches per month.I just want to know which format suits best for SEO.So if I am publishing my website after its launch should I publish it as http://domain.com format or http://www.domain.com format.
I also want to know if there is any advantage of being published in a specific format.also I want to know will the back links count if I post my website as http://domain.com and the link address in various forums and directories are http://www.domain.com pointing to my website.
Last but not the least will it make any difference if I post my website in www format or http alone format?

 

It doesn't make any difference http:// or www. You have to follow the same format throughout though and not to make any dublicat content under both formats

 

Choose one of them and keep using it, this will not affect your ranking

 

They are right, just choose between those format and do the right link building strategy to generate traffic to your site and for you to be indexed properly.

 

It doesn't matter as previous posters have said. There is no advantage to one over the other. It's personal preference.

But simply "picking one" and using it all of the time is NOT going to prevent URL canonicalization issues which lead to duplicate content and split page rank/link juice which will hinder your web pages' ability to rank. There are other decisions you need to make besides just www vs. non-www to prevent URL canonicalization issues. I you don't understand WHY your decisions are important, read the URL canonicalization post I linked to above.

There are other decisions you should make as well like whether to display default documents (for example, index.html, index.php, default.asp, default.aspx type pages) or to hide them... if you hide default documents then whether to show the trailing slash or hide it when referencing folders containing default document (i.e. http://example.com/folder or http://example.com/folder/)... and which pages should be http vs https (if applicable).

Once you have decided, you need to use something like Mod_Rewrite if on Apache web servers to implement code to enforce your URL canonicalization policy. You do this by 301 redirecting web pages from the non-canonical URLs to their corresponding canonical URLs.