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Merging and Unlinking Layers in Photoshop
One of Photoshop's many simple image editing features is the use of layers. This makes it easier to adjust, remove, and combine image elements.
Layers in Photoshop are like individual flat panes of glass stacked on top of each other. Each one contains a different piece of content.
You can resize, rearrange, and merge image layers in Photoshop to achieve the effect you want. Start by uploading an image to Photoshop. Select the layer you want to resize in the lower-right corner of the screen.