During laser engraving, the laser processes a shape, graphic or picture represented by a raster file such as a JPG or PNG. The process involves removing the material in a design in a horizontal motion, point by point, line by line, similar to the way a printer works. This processing method is called grid engraving.
You can engrave surfaces or shapes with many designs including photos, pictures, logos, inlays, fine to thick lettering, and stamps, to name a few.
More about the precise process of raster engraving