The what is in this case being the actual symbol that will be used. This is an interview with "Freeman Fly" of freemantv.com. Freeman is not a Christian but has spent his adult life exposing occult activities in multiple areas. In this case he's discussing (among other things like the striking resemblance of the Obama administration to the Stargate Atlantis crew) what the actual mark of the Beast will look like and what it represents. You will find the x inside a circle popping up in many things. It's called the "wolf's cross", and represents the four doors or rooms of judgment that are coming. Four horseman sound familiar? Interesting stuff to be sure.