Layers and the Layers Palette

The Mother of all Palettes
Without the layers palette, Photoshop would be a Windows program, it is the palette where most of the work gets done. With layers you can edit images without destroying the original pixels. You can also change the transparency and create subtle blending between layers which makes the difference between clip art and a composition.

Unfortunately, the layers palette also causes some confusion while you are trying to work on an image. Its easy to focus so much on the image window while you work that you tend to forget exactly which layer you are on. As a general rule, if you are having problems with getting a tool to work or trying to select something its usually because you are not working on the layer that you think you are.

Layers are usually thought of as plates of glass and you are basically looking on top of all the layers stacked up on one another in the image window. Transparent areas are represented with the checkered boxes, opaque areas are shown as is.