Layers are so central to GIMP that without them, this powerful application would be almost useless. Instead, we would only be able to use GIMP for simple drawings or minor photo touch-ups. All of GIMP’s more powerful and versatile features rely on layers.

When an image has multiple layers, the GIMP workspace acts as a stack of transparencies. Draw or paint on these transparencies, or arrange parts of an existing picture on separate layers. Set the layers’ visibility, or adjust how transparent they are or how they blend with other layers. Move them around the canvas and control their order in the layer stack. Duplicate a layer before changing it so an intact copy remains in case you make a mistake or want to use the layer for other purposes. Layering makes possible so many things that this chapter covers only the basic concepts, while later chapters combine these concepts with the tools and features provided by GIMP. In this chapter, we examine the Layers dialog, the Layers menu, and the Image: Layer menu.