Should I use Xorg or XFree86 for XServer?

[Doug Van Allen]

I'm going to install 5.3, but I now understand that sysinstall does
not handle in install of XServer.  It is a post-install duty.  I don't
know which is the better one to install-Xorg or XFree86??  Reading
some vague posts about this it seemed that people were using Xorg.

Thanks!