While the two are similar in nature and sometimes even synonymous, they do have important differences that are not always highlighted. Laser marking is leaving a permanent mark on the surface of the material only. Laser engraving, on the other hand, is leaving a permanent engraving in the material.
Laser marking oxidizes the surface of the material being treated when the engraving vaporizes the area it is aimed at, thus permanently removing a portion of the material to leave the engraving. As a result, the engraving will have significant depth. The depth can be controlled depending on how you use the laser beam. Read our laser engraving FAQ's and answers here.