Hello, I own a website and for some reason i want to redirect it from nonwww to www. Means i will still keep the same domain just the nonwww to www difference. I am asking now if this affects anything? SEO? SERP? Whatsoever which could cause loose of traffic from Google? Thanks!
Yeah, the www. is an extension of the main level domain and should be seen as a sort of sub category of the site. Many prefer to use that within a link when linking to your site and so you should look to 301 redirect the non www into the www. via the .htaccess file. There are guides on how to do that all over Google.
Yes, it will affect the SEO because your backlink was break down to two domain. However, it doesnt really affect much since most of the time we are getting link majority point to domain with www.
It is definately better to submit your preferance in Google webmaster and it does make a difference to ranking because you will be leaving link juice behind if you don't.
It is possible that it could affect your SERP results positively if you have links going to both the www and the non www version of the site. Now all those links will be consolidated in a single version, but unless you have lots of links going to both versions you probably will not notice much of a difference in your rankings. Just make sure the redirects are setup properly, otherwise it can have negative affects. Also, as others have stated, you should select your preference in Google Webmaster Tools.
it can affect your seo efforts since web visitors and your website performance is diverted into different links - www and non-www will be considered different links by search engines.. you need to do URL canonicalization
There will be a temporary effect until all the pages are updated in Google index. Then everything will become normal as before the changes.