Changing $sitename (Is $sitename just for printing?)

[wakewatcher]

I built (my first cms) on a hosted service with a generic url as provided by the hosting company.  After getting it going I bought a domain name from godaddy.com.  What I did was forwarded my new domain name to the cmsms site.  All seemed to work fine until I set up the selfregistration stuff and then the email sent etc refers to the original hosting site address.  Looking at the templates I see that what's getting printed is $sitename.  So my question is can I change $sitename somewhere to my domain name or is it used for things other than printing.  i.e. putting content in places.  thx.

[cubix]

first place that id look would be config.php in your root cms folder