This is the more common term, and simply defined, it means that in the process of creation of the brand, the material is to be removed or vaporized during the process. An example in our business is plastic engraving CO2 laser for signaling. This is often a plastic two-layer with a colour called the "cap" laminated to a contrast color is called the "kernel". The etching process removes the lid and exposes the core to create a sign that has an attractive appearance. There are also engraved in the metal processing. Typically used to ensure the permanence, the material is removed to create depth. This is usually a process reserved for 1, 064nm lasers of the wavelength (nd: YAG, for example) as these types of lasers paired well with the metals. When recording metals in this way, the laser is breaking the machined surface of the object, so that the oxidation or rust may occur as a result. This would be a question at the time of the test of feasibility. "do you want depth?" If so, do you realize that the base material could be oxidized? Depending on the response, the next option could be the laser marking.