Just a quick note about comma seperation in a URL:

The standards state a comma (,) character is reserved for special use in URLs, whilst they don't tell what the special use might be. As well the practical use of comma in URLs is much less strict. Many CMS use comma seperated lists in URLs to pass information to the URL target.

Redirecting whole websites or single webpages with mod_rewrite is a very important feature when doing search engine optimization (SEO) or when moving from one webserver or domain to another.

Redirection is usually done with a small block of code that is added to an .htaccess file in your websites root path. The code snippet looks like:

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

It is often misunderstood and the bulletin boards have hundrets of incomplete or wrong assumptions about Apache and mod_rewrite. That's why I decided to write an article about it.