Photoshop Adjustment Layers

So what are Photoshop Adjustment Layers and why are they different to any other layer? Is it better to use Adjustment Layers or apply an adjustment directly from the Image menu. If so, why so?

Adjustment layers are a part of the Adobe Photoshop none destructive workflow and so the answer is yes in most instances. They give you far more flexibility and control over image editing than working directly on a normal layer. You can apply a number of edits to them such as colour and tone changes without affecting pixel values. An adjustment layer sits ‘on top’ of the image layer as shown in the example below and the panel is turned on and off from the Window menu. Once an adjustment layer has been selected it will appear directly above the working layer.

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