Simple question, but I just can't figure out how to get the second site up.

Do I have to do a complete install of zencart in both domain folders or do I just link one domain folder to the other.

So in other words do I have to install zencart in /site1/ folder and then install and copy the same files to /site2/ or do I just link the second domain to /site1/ folder and it will know what do with it.

I know it's an easy question, just couldn't sort out how to go about it.

Thanks.