Dedicated Server/Game

Hi, I was currently looking into buying a game site, but the funny thing is that lets say you have a site called sitepointgames.com and the part of the site where the players go about trading whatever is called sitepointtrading.com
How do you go about merging those two site on a dedicated server?

I think Apache calls it Virtual Hosts. Both sites will have the same IP address (and server) and Apache will resolve based on the domain name. If you use cPanel it will handle it through Add on Domains. I’m sure other control panels and web servers would support the same thing.