Photoshop layers are probably the most important element in photoshop. Everything you create a text, image and any element in photoshop, you will create a layer for it.
Within layers and the layer panel, you can organize your file into folder and name each folder/layer.
You can also use layer styles. They give you the ability to do variety of changes to each individual layer such as drop shadow, border, gradient just to name a few.
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