What is Layer in Photoshop?

Layers are like stacked, transparent sheets of glass on which you can paint images. You can see through the transparent areas of a layer to the layers below. You can work on each layer independently, experimenting to create the effect you want. Each layer remains independent until you combine (merge) the layers. The bottommost layer in the Layers panel, the Background layer, is always locked (protected), meaning you cannot change its stacking order, blending mode, or opacity (unless you convert it into a regular layer).

About the Layers panel

The Layers panel (Window > Layers) lists all layers in an image, from the top layer to the Background layer at the bottom. In Expert mode, if you are working in the Custom Workspace, you can drag the Layers panel out and tab it with other panels.

The active layer, or the layer that you are working on, is highlighted for easy identification. As you work in an image, it’s a good idea to check which layer is active to make sure that the adjustments and edits you perform affect the correct layer. For example, if you choose a command and nothing seems to happen, check to make sure that you’re looking at the active layer.

Using the icons in the panel, you can accomplish many tasks—such as creating, hiding, linking, locking, and deleting layers. With some exceptions, your changes affect only the selected, or active, layer, which is highlighted.