CNC Plasma Cutters are intended for cutting out intricate designs from thin sheet metal. They use a plasma cutter which uses super-heated gas to vaporize metal.
If you boost a gas to extremely high temperatures, you get plasma. The energy begins to break apart the gas molecules, and the atoms begin to split. . In plasma, the electrons separate from the nucleus.
There are manually operated plasma torches that are hand held and look much like a welding torch. These same types of plasma torches can be mounted in a stepper motor controlled, 3 axis CNC machine, and use the same software workflow that a CNC router would use, to result in a very precise metal cutting machine.
Because of the high heat involved, and the spray of very hot sparks and vaporized metal, it isn't practical or safe to adapt a plasma torch to a CNC router structure that is made of wood or MDF, so most CNC plasma cutters are built with an open framework of welded steel, and they are operated in a more industrial type environment, over a concrete floor.
But once again, the same stepper motors, controller interface, computer and software will operate a CNC plasma cutter just fine.
An interesting bit of trivia...Almost 99 percent of all matter in the universe is plasma. It's not common on Earth because of its extremely high temperatures; but somewhere like the sun, it's the norm. On Earth, you find it in lightning, among other places.