Layers Layers are one of the most useful features of Photoshop. By using layers, you are able to keep different elements of the final image separate, apply affects to them, distort, filter etc. without necessarily affecting the other elements of the image. Think of layers as sheets of acetate stacked on top of one another. Where there is no image on a layer, you can see through to the layers below. Behind all of the layers is the background layer, which is not as easily alterable.
All layers share the same color attributes, number of channels, and the same resolution.
Each layer can be linked to another,have its opacity changed or, have affects applied to it. By clicking on the eye you can hide the layer. The layer that is being edited currently has a paintbrush in the column immediately to the right of the eye. The next column indicates whether or not an image is linked to another. The presence of a chain indicates that that layer is linked to another layer.