Is it bad to use both www. and non-www

Is it bad for SEO if your site loads under both www and non www?

If so, should I put this code into my .htaacess, will it solve my problem?

RewriteEngine On
RewriteCond %{HTTP_HOST} ^www.domain.com [NC]
RewriteRule ^(.*)$ http://domain.com/$1 [L,R=301]

 

It is better to only ever have content accessible from a single URL. So yes, redirecting from www.domain.com to domain.com or vice versa is highly recommended.

 

ok, and is that code correct? Like I don't want to mess up my .htaacess or anything by putting it in. This first line of my .htaacess is # -FrontPage-, do I put the code before or after that

 

It's better if you redirect to www.domain.com

 

yes it is bad with www and without www your domain because the links will divided into two urls..

 

using rel canonical can be used in this case.

 

Yes, it will influence your backlinks...
Some websites will link to www version of your domain and others may link to non-www version. This will result in backlink splitting.
You must set your preferred domain in Google webmaster tools and redirect one domain to your main domain.

 

I will affect your site. I would recommend to use the domain.com instead of the www.domain.com.
We have some experience with non www sites loading faster.

 

Here is the code to redirect non www version to www version of the website pages

RewriteEngine On
RewriteCond %{HTTP_HOST} !^www\.
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [R=301,L]

Unless you do this it will create content duplication issue.

 

yeah,it is really bad if you use both www and non-www as you domain. It will reduce your website's weight.

 

i see,If we use www and non www there is chances of getting split up with links am i right.

 

yes using both www and non www can affect your websites ranking in Google because Google see both as two different webpages. so try to use only single domain either with www or without www it depend on your choice. you can use redirection techniques or webmaster tool to handle this.

 

You should use 301 redirect for non-www to www.