Digital glass etching technique:

Surface etching: So named because you are only etching the surface of the glass. In addition, this type of etching is all done in one stage of applying chemical, which means that the designs produced are all 2 element designs. That is, all the designs are black and white.

Surface etching is the easiest technique to process and the fastest way to produce a finished etching on glass. The etched designs aren't as sophisticated as those from carving or shading.