To understand the importance of Layers, you have to try to imagine how much it sucked to work without them. Illustrator and Photoshop were great apps in the beginning, but the programs were extremely unforgiving. There was only one level of Undo, so you had to work with a copy of the original image, because if you made a mistake, it was set in stone. Your changes were permanent once you saved the document. If there was a typo, you had to start over from scratch. But Layers changed everything. They act like the clear sheets of vellum designers used to lay on top of an image to make edits to it without damaging the original underneath. In this guide, you will learn how Layers recreate this process, giving you the ability to edit without destroying the original.