Plasma Cutting was origionally developed in the 1950s for cutting stainless steel, copper and aluminum to replace flame cutting which was too aggresive or simply didn't work. Reason being oxy fuel methods, also called flame cutting, is not actually cutting as much as rapidly controlled rusting which isn't effective on materials that, don't actually rust like copper or aluminum.
Plasma may sound like a scientific word that's used relating to things most people never see, like in factories and labs. But actually plasma is very common, plasma is fire, it's lightning, it's neon lights, the aurora, and the sun; matter of fact it's all the stars in the universe and the most common state of matter we know of. It's actually it's own state of matter, along with solids, liquids and gases. Plasma requires two main factors energy and gas in order to form, in very non scientific terms when gas is exposed to an appropriate amount of energy it's electrons seperate from it's atoms or molecules creating a micro environment where ions and electrons coexit kind of violently and very brightly. Important to note however not all of the gas is ionized and once ionized the electrons still travel with it's parent atom or molecule so you can say it's directional in a sense. To harness that science and turn it into a technology was a huge feat.
Plasma cutting is achieved by creating an electric current from the plasma cutter through the work piece and through the ground wire, which completes a circuit. But theres a lot more going on than just some electricity. Plasma is superheated ionized gas, in our case compressed oxygen, which is forced out of a nozzle rapidly towards the base metal. An 'arch' is created between the electrode in the cutting head and the base metal ionizing some, but not all, of the air which creates plasma which is hot enough to melt through any metal. The remaining air literally blasts the molten material out of the backside of the cut and pushes it away from the work piece, effectively creating what we call a pierce; a hole in a piece of metal created by a lance of plasma and compressed air.
But that's just the first step, we use a CNC guided router compatible with a computer program in tandum with a 2D AutoCAD drawing program to cut out complex shapes out of sheets or plates of steel, aluminum, stainless steel, and any other conductive metals. And because of plasmas relatively straightforward principles, it scales up nicely, so we can cut anything from paper thin 22ga sheet metal up to 1in or 1 1/2 inch steel plating! And in whatever two dimensional shape you can think of! That gives us a lot of options.